When class name doesn't start with vagrant, prepend vagrant::root

Maintain existing structure for backwards compatibility and
isolate new plugin information which can be ignored when
using previous versions.

.gitignore

@@ -48,5 +48,10 @@ doc/
 .ruby-version
 .rvmrc
 
+# Extensions
+*.so
+*.bundle
+tmp/*
+
 # Box storage for spec
 test/vagrant-spec/boxes/*.box

.travis.yml

@@ -4,10 +4,17 @@ sudo: false
 
 cache: bundler
 
+before_install:
+  - which go
+  - sudo apt-get remove --purge golang-go
+  - sudo add-apt-repository ppa:gophers/archive -y
+  - sudo apt-get update -q
+  - sudo apt-get install golang-1.11-go -yq
+
 addons:
   apt:
     packages:
-    - bsdtar
+      - bsdtar
 
 rvm:
   - 2.3.8
@@ -22,5 +29,13 @@ branches:
 env:
   global:
     - NOKOGIRI_USE_SYSTEM_LIBRARIES=true
+    - GO111MODULE=on
+    - GOPATH=$HOME/go
+    - GOROOT=/usr/lib/go-1.11
+    - PATH=/usr/lib/go-1.11/bin:$PATH
 
-script: bundle exec rake test:unit
+script:
+  - go version
+  - go test ./...
+  - bundle exec rake compile
+  - bundle exec rake test:unit

Rakefile

@@ -1,5 +1,10 @@
 require 'rubygems'
 require 'bundler/setup'
+require 'rake/extensiontask'
+
+Rake::ExtensionTask.new "go-plugin" do |ext|
+  ext.lib_dir = "lib/vagrant/go_plugin"
+end
 
 # Immediately sync all stdout so that tools like buildbot can
 # immediately load in the output.

ext/go-plugin/extconf.rb

@@ -0,0 +1,68 @@
+lib = File.expand_path('./../../../lib', File.expand_path(__FILE__))
+$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
+
+require 'mkmf'
+require 'time'
+
+find_executable('go')
+
+go_version = /go version go(\d+\.\d+)/.match(`go version`).captures.first
+raise "'go' version >=1.5.0 is required, found go #{go_version}" unless Gem::Dependency.new('', '>=1.5.0').match?('', go_version)
+
+makefile = "Makefile"
+makefile_content = <<MFEND
+NAME := #{File.basename(File.dirname(File.expand_path(__FILE__)))}
+BINARY := ${NAME}.so
+
+V = 0
+Q1 = $(V:1=)
+Q = $(Q1:0=@)
+ECHO1 = $(V:1=@:)
+ECHO = $(ECHO1:0=@echo)
+
+SOURCEDIR=.
+SOURCES := $(shell find $(SOURCEDIR) -maxdepth 0 -name '*.go')
+
+VERSION=1.0
+BUILD_DATE=#{Time.now.iso8601}
+
+cflags= $(optflags) $(warnflags)
+optflags= -O3 -fno-fast-math
+warnflags= -Wall -Wextra -Wno-unused-parameter -Wno-parentheses -Wno-long-long -Wno-missing-field-initializers -Wunused-variable -Wpointer-arith -Wwrite-strings -Wimplicit-function-declaration -Wdiv-by-zero -Wdeprecated-declarations
+CCDLFLAGS= -fno-common
+INCFLAGS= -I#{RbConfig::CONFIG['rubyhdrdir']}/ -I#{RbConfig::CONFIG['rubyarchhdrdir']}/ -I$(SOURCEDIR)
+CFLAGS= $(CCDLFLAGS) $(cflags) -fno-common -pipe $(INCFLAGS)
+
+LDFLAGS=-L#{RbConfig::CONFIG['libdir']} #{RbConfig::CONFIG['LIBRUBYARG']}
+
+.DEFAULT_GOAL := $(BINARY)
+
+.PHONY: help
+help:
+  ${ECHO} ${VERSION}
+  ${ECHO} ${BUILD_DATE}
+
+all:
+  make clean
+  $(BINARY)
+
+$(BINARY): $(SOURCES)
+  CGO_CFLAGS="${CFLAGS}" CGO_LDFLAGS="${LDFLAGS}" go build -buildmode=c-shared -o ${BINARY} #{File.dirname(__FILE__)}/../../ext/${NAME}/
+
+.PHONY: install
+install:
+  # go install ${LDFLAGS} ./...
+
+.PHONY: clean
+clean:
+  if [ -f ${BINARY} ] ; then rm ${BINARY} ; fi
+  if [ -f lib/${BINARY} ] ; then rm lib/${BINARY} ; fi
+MFEND
+
+puts "creating Makefile"
+File.open(makefile, 'w') do |f|
+  f.write(makefile_content.gsub!(/(?:^|\G) {2}/m,"\t"))
+end
+
+
+$makefile_created = true

ext/go-plugin/go-plugin.go

@@ -0,0 +1,139 @@
+package main
+
+import (
+	"C"
+	"io/ioutil"
+	"os"
+
+	hclog "github.com/hashicorp/go-hclog"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/plugin"
+)
+
+var Plugins *plugin.VagrantPlugin
+
+//export Setup
+func Setup(enableLogger, timestamps bool, logLevel *C.char) bool {
+	lvl := to_gs(logLevel)
+	lopts := &hclog.LoggerOptions{Name: "vagrant"}
+	if enableLogger {
+		lopts.Output = os.Stderr
+	} else {
+		lopts.Output = ioutil.Discard
+	}
+	if !timestamps {
+		lopts.TimeFormat = " "
+	}
+	lopts.Level = hclog.LevelFromString(lvl)
+	vagrant.SetDefaultLogger(hclog.New(lopts))
+
+	if Plugins != nil {
+		Plugins.Logger.Error("plugins setup failure", "error", "already setup")
+		return false
+	}
+
+	Plugins = plugin.VagrantPluginInit()
+	return true
+}
+
+//export LoadPlugins
+func LoadPlugins(plgpath *C.char) bool {
+	if Plugins == nil {
+		vagrant.DefaultLogger().Error("cannot load plugins", "error", "not setup")
+		return false
+	}
+
+	p := to_gs(plgpath)
+	err := Plugins.LoadPlugins(p)
+	if err != nil {
+		Plugins.Logger.Error("failed loading plugins",
+			"path", p, "error", err)
+		return false
+	}
+	Plugins.Logger.Info("plugins successfully loaded", "path", p)
+	return true
+}
+
+//export Reset
+func Reset() {
+	if Plugins != nil {
+		Plugins.Logger.Info("resetting loaded plugins")
+		Teardown()
+		dirs := Plugins.PluginDirectories
+		Plugins.PluginDirectories = []string{}
+		for _, p := range dirs {
+			Plugins.LoadPlugins(p)
+		}
+	} else {
+		Plugins.Logger.Warn("plugin reset failure", "error", "not setup")
+	}
+}
+
+//export Teardown
+func Teardown() {
+	// only teardown if setup
+	if Plugins == nil {
+		vagrant.DefaultLogger().Error("cannot teardown plugins", "error", "not setup")
+		return
+	}
+	Plugins.Logger.Debug("tearing down any active plugins")
+	Plugins.Kill()
+	Plugins.Logger.Info("plugins have been halted")
+}
+
+//export ListProviders
+func ListProviders() *C.char {
+	list := map[string]interface{}{}
+	r := &Response{Result: list}
+	if Plugins == nil {
+		return r.Dump()
+	}
+	for n, p := range Plugins.Providers {
+		info := p.Provider.Info()
+		c := p.Client.ReattachConfig()
+		data := map[string]interface{}{
+			"network":     c.Addr.Network(),
+			"address":     c.Addr.String(),
+			"description": info.Description,
+			"priority":    info.Priority,
+		}
+		list[n] = data
+	}
+	r.Result = list
+	return r.Dump()
+}
+
+//export ListSyncedFolders
+func ListSyncedFolders() *C.char {
+	list := map[string]interface{}{}
+	r := &Response{Result: list}
+	if Plugins == nil {
+		return r.Dump()
+	}
+	for n, p := range Plugins.SyncedFolders {
+		info := p.SyncedFolder.Info()
+		c := p.Client.ReattachConfig()
+		data := map[string]interface{}{
+			"network":     c.Addr.Network(),
+			"address":     c.Addr.String(),
+			"description": info.Description,
+			"priority":    info.Priority,
+		}
+		list[n] = data
+	}
+	r.Result = list
+	return r.Dump()
+}
+
+// stub required for build
+func main() {}
+
+// helper to convert c string to go string
+func to_gs(s *C.char) string {
+	return C.GoString(s)
+}
+
+// helper to convert go string to c string
+func to_cs(s string) *C.char {
+	return C.CString(s)
+}

ext/go-plugin/response.go

@@ -0,0 +1,48 @@
+package main
+
+import (
+	"C"
+	"encoding/json"
+	"errors"
+	"fmt"
+)
+
+type Response struct {
+	Error  error       `json:"error"`
+	Result interface{} `json:"result"`
+}
+
+// Serialize the response into a JSON C string
+func (r *Response) Dump() *C.char {
+	tmp := map[string]interface{}{}
+	if r.Error != nil {
+		tmp["error"] = r.Error.Error()
+	} else {
+		tmp["error"] = nil
+	}
+	tmp["result"] = r.Result
+	result, err := json.Marshal(tmp)
+	if err != nil {
+		return to_cs(fmt.Sprintf(`{"error": "failed to encode response - %s"}`, err))
+	}
+	return to_cs(string(result[:]))
+}
+
+// Load a new response from a JSON C string
+func LoadResponse(s *C.char) (r *Response, err error) {
+	tmp := map[string]interface{}{}
+	st := []byte(to_gs(s))
+	r = &Response{}
+	err = json.Unmarshal(st, &tmp)
+	if tmp["error"] != nil {
+		e, ok := tmp["error"].(string)
+		if !ok {
+			err = errors.New(
+				fmt.Sprintf("cannot load error content - %s", tmp["error"]))
+			return
+		}
+		r.Error = errors.New(e)
+	}
+	r.Result = tmp["result"]
+	return
+}

ext/go-plugin/vagrant/box.go

@@ -0,0 +1,10 @@
+package vagrant
+
+type Box struct {
+	Name        string            `json:"name"`
+	Provider    string            `json:"provider"`
+	Version     string            `json:"version"`
+	Directory   string            `json:"directory"`
+	Metadata    map[string]string `json:"metadata"`
+	MetadataURL string            `json:"metadata_url"`
+}

ext/go-plugin/vagrant/capabilities.go

@@ -0,0 +1,61 @@
+package vagrant
+
+import (
+	"context"
+)
+
+type SystemCapability struct {
+	Name     string `json:"name"`
+	Platform string `json:"platform"`
+}
+
+type ProviderCapability struct {
+	Name     string `json:"name"`
+	Provider string `json:"provider"`
+}
+
+type GuestCapabilities interface {
+	GuestCapabilities() (caps []SystemCapability, err error)
+	GuestCapability(ctx context.Context, cap *SystemCapability, args interface{}, machine *Machine) (result interface{}, err error)
+}
+
+type HostCapabilities interface {
+	HostCapabilities() (caps []SystemCapability, err error)
+	HostCapability(ctx context.Context, cap *SystemCapability, args interface{}, env *Environment) (result interface{}, err error)
+}
+
+type ProviderCapabilities interface {
+	ProviderCapabilities() (caps []ProviderCapability, err error)
+	ProviderCapability(ctx context.Context, cap *ProviderCapability, args interface{}, machine *Machine) (result interface{}, err error)
+}
+
+type NoGuestCapabilities struct{}
+type NoHostCapabilities struct{}
+type NoProviderCapabilities struct{}
+
+func (g *NoGuestCapabilities) GuestCapabilities() (caps []SystemCapability, err error) {
+	caps = make([]SystemCapability, 0)
+	return
+}
+
+func (g *NoGuestCapabilities) GuestCapability(x context.Context, c *SystemCapability, a interface{}, m *Machine) (r interface{}, err error) {
+	return
+}
+
+func (h *NoHostCapabilities) HostCapabilities() (caps []SystemCapability, err error) {
+	caps = make([]SystemCapability, 0)
+	return
+}
+
+func (h *NoHostCapabilities) HostCapability(x context.Context, c *SystemCapability, a interface{}, e *Environment) (r interface{}, err error) {
+	return
+}
+
+func (p *NoProviderCapabilities) ProviderCapabilities() (caps []ProviderCapability, err error) {
+	caps = make([]ProviderCapability, 0)
+	return
+}
+
+func (p *NoProviderCapabilities) ProviderCapability(x context.Context, cap *ProviderCapability, args interface{}, machine *Machine) (result interface{}, err error) {
+	return
+}

ext/go-plugin/vagrant/capabilities_test.go

@@ -0,0 +1,78 @@
+package vagrant
+
+import (
+	"context"
+	"testing"
+)
+
+func TestNoGuestCapabilities(t *testing.T) {
+	g := NoGuestCapabilities{}
+	caps, err := g.GuestCapabilities()
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	if len(caps) != 0 {
+		t.Fatalf("guest capabilities should be empty")
+	}
+}
+
+func TestNoGuestCapability(t *testing.T) {
+	g := NoGuestCapabilities{}
+	m := &Machine{}
+	cap := &SystemCapability{"Test", "Test"}
+	r, err := g.GuestCapability(context.Background(), cap, "args", m)
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	if r != nil {
+		t.Fatalf("capability returned unexpected result")
+	}
+}
+
+func TestNoHostCapabilities(t *testing.T) {
+	h := NoHostCapabilities{}
+	caps, err := h.HostCapabilities()
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	if len(caps) != 0 {
+		t.Fatalf("host capabilities should be empty")
+	}
+}
+
+func TestNoHostCapability(t *testing.T) {
+	h := NoHostCapabilities{}
+	e := &Environment{}
+	cap := &SystemCapability{"Test", "Test"}
+	r, err := h.HostCapability(context.Background(), cap, "args", e)
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	if r != nil {
+		t.Fatalf("capability returned unexpected result")
+	}
+}
+
+func TestNoProviderCapabilities(t *testing.T) {
+	p := NoProviderCapabilities{}
+	caps, err := p.ProviderCapabilities()
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	if len(caps) != 0 {
+		t.Fatalf("provider capabilities should be empty")
+	}
+}
+
+func TestNoProviderCapability(t *testing.T) {
+	p := NoProviderCapabilities{}
+	m := &Machine{}
+	cap := &ProviderCapability{"Test", "Test"}
+	r, err := p.ProviderCapability(context.Background(), cap, "args", m)
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	if r != nil {
+		t.Fatalf("capability returned unexpected result")
+	}
+}

ext/go-plugin/vagrant/communicator/command.go

@@ -0,0 +1,202 @@
+package communicator
+
+import (
+	"fmt"
+	"io"
+	"strings"
+	"sync"
+	"unicode"
+
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+	"github.com/mitchellh/iochan"
+)
+
+// CmdDisconnect is a sentinel value to indicate a RemoteCmd
+// exited because the remote side disconnected us.
+const CmdDisconnect int = 2300218
+
+// Cmd represents a remote command being prepared or run.
+type Cmd struct {
+	// Command is the command to run remotely. This is executed as if
+	// it were a shell command, so you are expected to do any shell escaping
+	// necessary.
+	Command string
+
+	// Stdin specifies the process's standard input. If Stdin is
+	// nil, the process reads from an empty bytes.Buffer.
+	Stdin io.Reader
+
+	// Stdout and Stderr represent the process's standard output and
+	// error.
+	//
+	// If either is nil, it will be set to ioutil.Discard.
+	Stdout io.Writer
+	Stderr io.Writer
+
+	// Once Wait returns, his will contain the exit code of the process.
+	exitStatus int
+
+	// Internal fields
+	exitCh chan struct{}
+
+	// err is used to store any error reported by the Communicator during
+	// execution.
+	err error
+
+	// This thing is a mutex, lock when making modifications concurrently
+	sync.Mutex
+}
+
+// Init must be called by the Communicator before executing the command.
+func (c *Cmd) Init() {
+	c.Lock()
+	defer c.Unlock()
+
+	c.exitCh = make(chan struct{})
+}
+
+// SetExitStatus stores the exit status of the remote command as well as any
+// communicator related error. SetExitStatus then unblocks any pending calls
+// to Wait.
+// This should only be called by communicators executing the remote.Cmd.
+func (c *Cmd) SetExitStatus(status int, err error) {
+	c.Lock()
+	defer c.Unlock()
+
+	c.exitStatus = status
+	c.err = err
+
+	close(c.exitCh)
+}
+
+// StartWithUi runs the remote command and streams the output to any
+// configured Writers for stdout/stderr, while also writing each line
+// as it comes to a Ui.
+func (r *Cmd) StartWithUi(c Communicator, ui vagrant.Ui) error {
+	stdout_r, stdout_w := io.Pipe()
+	stderr_r, stderr_w := io.Pipe()
+	defer stdout_w.Close()
+	defer stderr_w.Close()
+
+	// Retain the original stdout/stderr that we can replace back in.
+	originalStdout := r.Stdout
+	originalStderr := r.Stderr
+	defer func() {
+		r.Lock()
+		defer r.Unlock()
+
+		r.Stdout = originalStdout
+		r.Stderr = originalStderr
+	}()
+
+	// Set the writers for the output so that we get it streamed to us
+	if r.Stdout == nil {
+		r.Stdout = stdout_w
+	} else {
+		r.Stdout = io.MultiWriter(r.Stdout, stdout_w)
+	}
+
+	if r.Stderr == nil {
+		r.Stderr = stderr_w
+	} else {
+		r.Stderr = io.MultiWriter(r.Stderr, stderr_w)
+	}
+
+	// Start the command
+	if err := c.Start(r); err != nil {
+		return err
+	}
+
+	// Create the channels we'll use for data
+	exitCh := make(chan struct{})
+	stdoutCh := iochan.DelimReader(stdout_r, '\n')
+	stderrCh := iochan.DelimReader(stderr_r, '\n')
+
+	// Start the goroutine to watch for the exit
+	go func() {
+		defer close(exitCh)
+		defer stdout_w.Close()
+		defer stderr_w.Close()
+		r.Wait()
+	}()
+
+	// Loop and get all our output
+OutputLoop:
+	for {
+		select {
+		case output := <-stderrCh:
+			if output != "" {
+				ui.Say(r.cleanOutputLine(output))
+			}
+		case output := <-stdoutCh:
+			if output != "" {
+				ui.Say(r.cleanOutputLine(output))
+			}
+		case <-exitCh:
+			break OutputLoop
+		}
+	}
+
+	// Make sure we finish off stdout/stderr because we may have gotten
+	// a message from the exit channel before finishing these first.
+	for output := range stdoutCh {
+		ui.Say(r.cleanOutputLine(output))
+	}
+
+	for output := range stderrCh {
+		ui.Say(r.cleanOutputLine(output))
+	}
+
+	return nil
+}
+
+// Wait waits for the remote command to complete.
+// Wait may return an error from the communicator, or an ExitError if the
+// process exits with a non-zero exit status.
+func (c *Cmd) Wait() error {
+	<-c.exitCh
+
+	c.Lock()
+	defer c.Unlock()
+
+	if c.err != nil || c.exitStatus != 0 {
+		return &ExitError{
+			Command:    c.Command,
+			ExitStatus: c.exitStatus,
+			Err:        c.err,
+		}
+	}
+
+	return nil
+}
+
+// cleanOutputLine cleans up a line so that '\r' don't muck up the
+// UI output when we're reading from a remote command.
+func (r *Cmd) cleanOutputLine(line string) string {
+	// Trim surrounding whitespace
+	line = strings.TrimRightFunc(line, unicode.IsSpace)
+
+	// Trim up to the first carriage return, since that text would be
+	// lost anyways.
+	idx := strings.LastIndex(line, "\r")
+	if idx > -1 {
+		line = line[idx+1:]
+	}
+
+	return line
+}
+
+// ExitError is returned by Wait to indicate and error executing the remote
+// command, or a non-zero exit status.
+type ExitError struct {
+	Command    string
+	ExitStatus int
+	Err        error
+}
+
+func (e *ExitError) Error() string {
+	if e.Err != nil {
+		return fmt.Sprintf("error executing %q: %v", e.Command, e.Err)
+	}
+	return fmt.Sprintf("%q exit status: %d", e.Command, e.ExitStatus)
+}

ext/go-plugin/vagrant/communicator/command_test.go

@@ -0,0 +1 @@
+package communicator

ext/go-plugin/vagrant/communicator/communicator.go

@@ -0,0 +1,117 @@
+package communicator
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"sync/atomic"
+	"time"
+
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+)
+
+type Communicator interface {
+	Connect() error
+	Disconnect() error
+	Timeout() time.Duration
+	Start(*Cmd) error
+	Download(path string, output io.Writer) error
+	DownloadDir(dst, src string, excludes []string) error
+	Upload(dst string, src io.Reader, srcinfo *os.FileInfo) error
+	UploadDir(dst, src string, excludes []string) error
+}
+
+// maxBackoffDelay is the maximum delay between retry attempts
+var maxBackoffDelay = 20 * time.Second
+var initialBackoffDelay = time.Second
+var logger = vagrant.DefaultLogger().Named("communicator")
+
+// Fatal is an interface that error values can return to halt Retry
+type Fatal interface {
+	FatalError() error
+}
+
+// Retry retries the function f until it returns a nil error, a Fatal error, or
+// the context expires.
+func Retry(ctx context.Context, f func() error) error {
+	// container for atomic error value
+	type errWrap struct {
+		E error
+	}
+
+	// Try the function in a goroutine
+	var errVal atomic.Value
+	doneCh := make(chan struct{})
+	go func() {
+		defer close(doneCh)
+
+		delay := time.Duration(0)
+		for {
+			// If our context ended, we want to exit right away.
+			select {
+			case <-ctx.Done():
+				return
+			case <-time.After(delay):
+			}
+
+			// Try the function call
+			err := f()
+
+			// return if we have no error, or a FatalError
+			done := false
+			switch e := err.(type) {
+			case nil:
+				done = true
+			case Fatal:
+				err = e.FatalError()
+				done = true
+			}
+
+			errVal.Store(errWrap{err})
+
+			if done {
+				return
+			}
+
+			logger.Warn("retryable error", "error", err)
+
+			delay *= 2
+
+			if delay == 0 {
+				delay = initialBackoffDelay
+			}
+
+			if delay > maxBackoffDelay {
+				delay = maxBackoffDelay
+			}
+
+			logger.Info("sleeping for retry", "duration", delay)
+		}
+	}()
+
+	// Wait for completion
+	select {
+	case <-ctx.Done():
+	case <-doneCh:
+	}
+
+	var lastErr error
+	// Check if we got an error executing
+	if ev, ok := errVal.Load().(errWrap); ok {
+		lastErr = ev.E
+	}
+
+	// Check if we have a context error to check if we're interrupted or timeout
+	switch ctx.Err() {
+	case context.Canceled:
+		return fmt.Errorf("interrupted - last error: %v", lastErr)
+	case context.DeadlineExceeded:
+		return fmt.Errorf("timeout - last error: %v", lastErr)
+	}
+
+	if lastErr != nil {
+		return lastErr
+	}
+	return nil
+}

ext/go-plugin/vagrant/communicator/none/communicator.go

@@ -0,0 +1,59 @@
+package none
+
+import (
+	"errors"
+	"io"
+	"os"
+	"time"
+
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/communicator"
+)
+
+type Communicator struct {
+	config string
+}
+
+// Creates a null vagrant.Communicator implementation. This takes
+// an already existing configuration.
+func New(config string) (result *Communicator, err error) {
+	// Establish an initial connection and connect
+	result = &Communicator{
+		config: config,
+	}
+
+	return
+}
+
+func (c *Communicator) Connect() (err error) {
+	return
+}
+
+func (c *Communicator) Disconnect() (err error) {
+	return
+}
+
+func (c *Communicator) Start(cmd *communicator.Cmd) (err error) {
+	cmd.Init()
+	cmd.SetExitStatus(0, nil)
+	return
+}
+
+func (c *Communicator) Upload(path string, input io.Reader, fi *os.FileInfo) error {
+	return errors.New("Upload is not implemented when communicator = 'none'")
+}
+
+func (c *Communicator) UploadDir(dst string, src string, excl []string) error {
+	return errors.New("UploadDir is not implemented when communicator = 'none'")
+}
+
+func (c *Communicator) Download(path string, output io.Writer) error {
+	return errors.New("Download is not implemented when communicator = 'none'")
+}
+
+func (c *Communicator) DownloadDir(dst string, src string, excl []string) error {
+	return errors.New("DownloadDir is not implemented when communicator = 'none'")
+}
+
+func (c *Communicator) Timeout() time.Duration {
+	return 0
+}

ext/go-plugin/vagrant/communicator/none/communicator_test.go

@@ -0,0 +1,12 @@
+package none
+
+import (
+	"testing"
+
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/communicator"
+)
+
+func TestCommIsCommunicator(t *testing.T) {
+	// Force failure with explanation of why it's not valid
+	var _ communicator.Communicator = new(Communicator)
+}

ext/go-plugin/vagrant/communicator/ssh/communicator.go

@@ -0,0 +1,949 @@
+package ssh
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/communicator"
+	"github.com/pkg/sftp"
+	"golang.org/x/crypto/ssh"
+	"golang.org/x/crypto/ssh/agent"
+)
+
+// ErrHandshakeTimeout is returned from New() whenever we're unable to establish
+// an ssh connection within a certain timeframe. By default the handshake time-
+// out period is 1 minute. You can change it with Config.HandshakeTimeout.
+var ErrHandshakeTimeout = fmt.Errorf("Timeout during SSH handshake")
+
+var logger = vagrant.DefaultLogger().Named("communicator.ssh")
+
+type Communicator struct {
+	client  *ssh.Client
+	config  *Config
+	conn    net.Conn
+	address string
+}
+
+// Config is the structure used to configure the SSH communicator.
+type Config struct {
+	// The configuration of the Go SSH connection
+	SSHConfig *ssh.ClientConfig
+
+	// Connection returns a new connection. The current connection
+	// in use will be closed as part of the Close method, or in the
+	// case an error occurs.
+	Connection func() (net.Conn, error)
+
+	// Pty, if true, will request a pty from the remote end.
+	Pty bool
+
+	// DisableAgentForwarding, if true, will not forward the SSH agent.
+	DisableAgentForwarding bool
+
+	// HandshakeTimeout limits the amount of time we'll wait to handshake before
+	// saying the connection failed.
+	HandshakeTimeout time.Duration
+
+	// UseSftp, if true, sftp will be used instead of scp for file transfers
+	UseSftp bool
+
+	// KeepAliveInterval sets how often we send a channel request to the
+	// server. A value < 0 disables.
+	KeepAliveInterval time.Duration
+
+	// Timeout is how long to wait for a read or write to succeed.
+	Timeout time.Duration
+}
+
+// Creates a new vagrant.Communicator implementation over SSH. This takes
+// an already existing TCP connection and SSH configuration.
+func New(address string, config *Config) (result *Communicator, err error) {
+	// Establish an initial connection and connect
+	result = &Communicator{
+		config:  config,
+		address: address,
+	}
+
+	// reset the logger in case custom default has been set
+	logger = vagrant.DefaultLogger().Named("communicator.ssh")
+
+	return
+}
+
+func (c *Communicator) Connect() error {
+	return c.reconnect()
+}
+
+func (c *Communicator) Disconnect() (err error) {
+	if c.conn != nil {
+		logger.Info("closing connection")
+		err = c.conn.Close()
+	} else {
+		err = errors.New("No connection currently established to close")
+	}
+	return
+}
+
+func (c *Communicator) Timeout() time.Duration {
+	return c.config.Timeout
+}
+
+func (c *Communicator) Start(cmd *communicator.Cmd) (err error) {
+	session, err := c.newSession()
+	if err != nil {
+		return
+	}
+
+	// Setup our session
+	session.Stdin = cmd.Stdin
+	session.Stdout = cmd.Stdout
+	session.Stderr = cmd.Stderr
+
+	if c.config.Pty {
+		// Request a PTY
+		termModes := ssh.TerminalModes{
+			ssh.ECHO:          0,     // do not echo
+			ssh.TTY_OP_ISPEED: 14400, // input speed = 14.4kbaud
+			ssh.TTY_OP_OSPEED: 14400, // output speed = 14.4kbaud
+		}
+
+		if err = session.RequestPty("xterm", 40, 80, termModes); err != nil {
+			return
+		}
+	}
+
+	logger.Debug("starting remote command", "command", cmd.Command)
+	err = session.Start(cmd.Command + "\n")
+	if err != nil {
+		return
+	}
+
+	go func() {
+		if c.config.KeepAliveInterval <= 0 {
+			return
+		}
+		c := time.NewTicker(c.config.KeepAliveInterval)
+		defer c.Stop()
+		for range c.C {
+			_, err := session.SendRequest("keepalive@vagrantup.com", true, nil)
+			if err != nil {
+				return
+			}
+		}
+	}()
+
+	// Start a goroutine to wait for the session to end and set the
+	// exit boolean and status.
+	go func() {
+		defer session.Close()
+
+		err := session.Wait()
+		exitStatus := 0
+		if err != nil {
+			switch err.(type) {
+			case *ssh.ExitError:
+				exitStatus = err.(*ssh.ExitError).ExitStatus()
+				logger.Error("remote command exited non-zero",
+					"exitcode", exitStatus, "command", cmd.Command)
+			case *ssh.ExitMissingError:
+				logger.Error("remote command exited without exit status or exit signal",
+					"command", cmd.Command)
+				exitStatus = communicator.CmdDisconnect
+			default:
+				logger.Error("error waiting for ssh session", "error", err)
+			}
+		}
+		cmd.SetExitStatus(exitStatus, err)
+	}()
+	return
+}
+
+func (c *Communicator) Upload(path string, input io.Reader, fi *os.FileInfo) error {
+	if c.config.UseSftp {
+		return c.sftpUploadSession(path, input, fi)
+	} else {
+		return c.scpUploadSession(path, input, fi)
+	}
+}
+
+func (c *Communicator) UploadDir(dst string, src string, excl []string) error {
+	logger.Debug("uploading directory", "source", src, "destination", dst)
+	if c.config.UseSftp {
+		return c.sftpUploadDirSession(dst, src, excl)
+	} else {
+		return c.scpUploadDirSession(dst, src, excl)
+	}
+}
+
+func (c *Communicator) DownloadDir(src string, dst string, excl []string) error {
+	logger.Debug("downloading directory", "source", src, "destination", dst)
+	scpFunc := func(w io.Writer, stdoutR *bufio.Reader) error {
+		dirStack := []string{dst}
+		for {
+			fmt.Fprint(w, "\x00")
+
+			// read file info
+			fi, err := stdoutR.ReadString('\n')
+			if err != nil {
+				return err
+			}
+
+			if len(fi) < 0 {
+				return fmt.Errorf("empty response from server")
+			}
+
+			switch fi[0] {
+			case '\x01', '\x02':
+				return fmt.Errorf("%s", fi[1:])
+			case 'C', 'D':
+				break
+			case 'E':
+				dirStack = dirStack[:len(dirStack)-1]
+				if len(dirStack) == 0 {
+					fmt.Fprint(w, "\x00")
+					return nil
+				}
+				continue
+			default:
+				return fmt.Errorf("unexpected server response (%x)", fi[0])
+			}
+
+			var mode int64
+			var size int64
+			var name string
+			logger.Debug("download directory", "str", fi)
+			n, err := fmt.Sscanf(fi[1:], "%o %d %s", &mode, &size, &name)
+			if err != nil || n != 3 {
+				return fmt.Errorf("can't parse server response (%s)", fi)
+			}
+			if size < 0 {
+				return fmt.Errorf("negative file size")
+			}
+
+			logger.Debug("download directory", "mode", mode, "size", size, "name", name)
+
+			dst = filepath.Join(dirStack...)
+			switch fi[0] {
+			case 'D':
+				err = os.MkdirAll(filepath.Join(dst, name), os.FileMode(mode))
+				if err != nil {
+					return err
+				}
+				dirStack = append(dirStack, name)
+				continue
+			case 'C':
+				fmt.Fprint(w, "\x00")
+				err = scpDownloadFile(filepath.Join(dst, name), stdoutR, size, os.FileMode(mode))
+				if err != nil {
+					return err
+				}
+			}
+
+			if err := checkSCPStatus(stdoutR); err != nil {
+				return err
+			}
+		}
+	}
+	return c.scpSession("scp -vrf "+src, scpFunc)
+}
+
+func (c *Communicator) Download(path string, output io.Writer) error {
+	if c.config.UseSftp {
+		return c.sftpDownloadSession(path, output)
+	}
+	return c.scpDownloadSession(path, output)
+}
+
+func (c *Communicator) newSession() (session *ssh.Session, err error) {
+	logger.Debug("opening new ssh session")
+	if c.client == nil {
+		err = errors.New("client not available")
+	} else {
+		session, err = c.client.NewSession()
+	}
+
+	if err != nil {
+		logger.Error("ssh session open failure", "error", err)
+		if err := c.reconnect(); err != nil {
+			return nil, err
+		}
+
+		if c.client == nil {
+			return nil, errors.New("client not available")
+		} else {
+			return c.client.NewSession()
+		}
+	}
+
+	return session, nil
+}
+
+func (c *Communicator) reconnect() (err error) {
+	// Ignore errors here because we don't care if it fails
+	c.Disconnect()
+	// Set the conn and client to nil since we'll recreate it
+	c.conn = nil
+	c.client = nil
+
+	logger.Debug("reconnection to tcp connection for ssh")
+	c.conn, err = c.config.Connection()
+	if err != nil {
+		// Explicitly set this to the REAL nil. Connection() can return
+		// a nil implementation of net.Conn which will make the
+		// "if c.conn == nil" check fail above. Read here for more information
+		// on this psychotic language feature:
+		//
+		// http://golang.org/doc/faq#nil_error
+		c.conn = nil
+
+		logger.Error("reconnection failure", "error", err)
+		return
+	}
+
+	if c.config.Timeout > 0 {
+		c.conn = &timeoutConn{c.conn, c.config.Timeout, c.config.Timeout}
+	}
+
+	logger.Debug("handshaking with ssh")
+
+	// Default timeout to 1 minute if it wasn't specified (zero value). For
+	// when you need to handshake from low orbit.
+	var duration time.Duration
+	if c.config.HandshakeTimeout == 0 {
+		duration = 1 * time.Minute
+	} else {
+		duration = c.config.HandshakeTimeout
+	}
+
+	connectionEstablished := make(chan struct{}, 1)
+
+	var sshConn ssh.Conn
+	var sshChan <-chan ssh.NewChannel
+	var req <-chan *ssh.Request
+
+	go func() {
+		sshConn, sshChan, req, err = ssh.NewClientConn(c.conn, c.address, c.config.SSHConfig)
+		close(connectionEstablished)
+	}()
+
+	select {
+	case <-connectionEstablished:
+		// We don't need to do anything here. We just want select to block until
+		// we connect or timeout.
+	case <-time.After(duration):
+		if c.conn != nil {
+			c.conn.Close()
+		}
+		if sshConn != nil {
+			sshConn.Close()
+		}
+		return ErrHandshakeTimeout
+	}
+
+	if err != nil {
+		return
+	}
+	logger.Debug("handshake complete")
+	if sshConn != nil {
+		c.client = ssh.NewClient(sshConn, sshChan, req)
+	}
+	c.connectToAgent()
+
+	return
+}
+
+func (c *Communicator) connectToAgent() {
+	if c.client == nil {
+		return
+	}
+
+	if c.config.DisableAgentForwarding {
+		logger.Info("SSH agent forwarding is disabled")
+		return
+	}
+
+	// open connection to the local agent
+	socketLocation := os.Getenv("SSH_AUTH_SOCK")
+	if socketLocation == "" {
+		logger.Info("no local agent socket, will not connect agent")
+		return
+	}
+	agentConn, err := net.Dial("unix", socketLocation)
+	if err != nil {
+		logger.Error("could not connect to local agent socket", "path", socketLocation)
+		return
+	}
+
+	// create agent and add in auth
+	forwardingAgent := agent.NewClient(agentConn)
+	if forwardingAgent == nil {
+		logger.Error("could not create agent client")
+		agentConn.Close()
+		return
+	}
+
+	// add callback for forwarding agent to SSH config
+	// XXX - might want to handle reconnects appending multiple callbacks
+	auth := ssh.PublicKeysCallback(forwardingAgent.Signers)
+	c.config.SSHConfig.Auth = append(c.config.SSHConfig.Auth, auth)
+	agent.ForwardToAgent(c.client, forwardingAgent)
+
+	// Setup a session to request agent forwarding
+	session, err := c.newSession()
+	if err != nil {
+		return
+	}
+	defer session.Close()
+
+	err = agent.RequestAgentForwarding(session)
+	if err != nil {
+		logger.Error("request agent forwarding failed", "error", err)
+		return
+	}
+
+	logger.Info("agent forwarding enabled")
+	return
+}
+
+func (c *Communicator) sftpUploadSession(path string, input io.Reader, fi *os.FileInfo) error {
+	sftpFunc := func(client *sftp.Client) error {
+		return c.sftpUploadFile(path, input, client, fi)
+	}
+
+	return c.sftpSession(sftpFunc)
+}
+
+func (c *Communicator) sftpUploadFile(path string, input io.Reader, client *sftp.Client, fi *os.FileInfo) error {
+	logger.Debug("sftp uploading", "path", path)
+	f, err := client.Create(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	if _, err = io.Copy(f, input); err != nil {
+		return err
+	}
+
+	if fi != nil && (*fi).Mode().IsRegular() {
+		mode := (*fi).Mode().Perm()
+		err = client.Chmod(path, mode)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (c *Communicator) sftpUploadDirSession(dst string, src string, excl []string) error {
+	sftpFunc := func(client *sftp.Client) error {
+		rootDst := dst
+		if src[len(src)-1] != '/' {
+			logger.Debug("no trailing slash, creating the source directory name")
+			rootDst = filepath.Join(dst, filepath.Base(src))
+		}
+		walkFunc := func(path string, info os.FileInfo, err error) error {
+			if err != nil {
+				return err
+			}
+			// Calculate the final destination using the
+			// base source and root destination
+			relSrc, err := filepath.Rel(src, path)
+			if err != nil {
+				return err
+			}
+			finalDst := filepath.Join(rootDst, relSrc)
+
+			// In Windows, Join uses backslashes which we don't want to get
+			// to the sftp server
+			finalDst = filepath.ToSlash(finalDst)
+
+			// Skip the creation of the target destination directory since
+			// it should exist and we might not even own it
+			if finalDst == dst {
+				return nil
+			}
+
+			return c.sftpVisitFile(finalDst, path, info, client)
+		}
+
+		return filepath.Walk(src, walkFunc)
+	}
+
+	return c.sftpSession(sftpFunc)
+}
+
+func (c *Communicator) sftpMkdir(path string, client *sftp.Client, fi os.FileInfo) error {
+	logger.Debug("sftp create directory", "path", path)
+
+	if err := client.Mkdir(path); err != nil {
+		// Do not consider it an error if the directory existed
+		remoteFi, fiErr := client.Lstat(path)
+		if fiErr != nil || !remoteFi.IsDir() {
+			return err
+		}
+	}
+
+	mode := fi.Mode().Perm()
+	if err := client.Chmod(path, mode); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (c *Communicator) sftpVisitFile(dst string, src string, fi os.FileInfo, client *sftp.Client) error {
+	if !fi.IsDir() {
+		f, err := os.Open(src)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+		return c.sftpUploadFile(dst, f, client, &fi)
+	} else {
+		err := c.sftpMkdir(dst, client, fi)
+		return err
+	}
+}
+
+func (c *Communicator) sftpDownloadSession(path string, output io.Writer) error {
+	sftpFunc := func(client *sftp.Client) error {
+		f, err := client.Open(path)
+		if err != nil {
+			return err
+		}
+		defer f.Close()
+
+		if _, err = io.Copy(output, f); err != nil {
+			return err
+		}
+
+		return nil
+	}
+
+	return c.sftpSession(sftpFunc)
+}
+
+func (c *Communicator) sftpSession(f func(*sftp.Client) error) error {
+	client, err := c.newSftpClient()
+	if err != nil {
+		return fmt.Errorf("sftpSession error: %s", err.Error())
+	}
+	defer client.Close()
+
+	return f(client)
+}
+
+func (c *Communicator) newSftpClient() (*sftp.Client, error) {
+	session, err := c.newSession()
+	if err != nil {
+		return nil, err
+	}
+
+	if err := session.RequestSubsystem("sftp"); err != nil {
+		return nil, err
+	}
+
+	pw, err := session.StdinPipe()
+	if err != nil {
+		return nil, err
+	}
+	pr, err := session.StdoutPipe()
+	if err != nil {
+		return nil, err
+	}
+
+	// Capture stdout so we can return errors to the user
+	var stdout bytes.Buffer
+	tee := io.TeeReader(pr, &stdout)
+	client, err := sftp.NewClientPipe(tee, pw)
+	if err != nil && stdout.Len() > 0 {
+		logger.Error("upload failed", "error", stdout.Bytes())
+	}
+
+	return client, err
+}
+
+func (c *Communicator) scpUploadSession(path string, input io.Reader, fi *os.FileInfo) error {
+
+	// The target directory and file for talking the SCP protocol
+	target_dir := filepath.Dir(path)
+	target_file := filepath.Base(path)
+
+	// On windows, filepath.Dir uses backslash separators (ie. "\tmp").
+	// This does not work when the target host is unix.  Switch to forward slash
+	// which works for unix and windows
+	target_dir = filepath.ToSlash(target_dir)
+
+	// Escape spaces in remote directory
+	target_dir = strings.Replace(target_dir, " ", "\\ ", -1)
+
+	scpFunc := func(w io.Writer, stdoutR *bufio.Reader) error {
+		return scpUploadFile(target_file, input, w, stdoutR, fi)
+	}
+
+	return c.scpSession("scp -vt "+target_dir, scpFunc)
+}
+
+func (c *Communicator) scpUploadDirSession(dst string, src string, excl []string) error {
+	scpFunc := func(w io.Writer, r *bufio.Reader) error {
+		uploadEntries := func() error {
+			f, err := os.Open(src)
+			if err != nil {
+				return err
+			}
+			defer f.Close()
+
+			entries, err := f.Readdir(-1)
+			if err != nil {
+				return err
+			}
+
+			return scpUploadDir(src, entries, w, r)
+		}
+
+		if src[len(src)-1] != '/' {
+			logger.Debug("no trailing slash, creating the source directory name")
+			fi, err := os.Stat(src)
+			if err != nil {
+				return err
+			}
+			return scpUploadDirProtocol(filepath.Base(src), w, r, uploadEntries, fi)
+		} else {
+			// Trailing slash, so only upload the contents
+			return uploadEntries()
+		}
+	}
+
+	return c.scpSession("scp -rvt "+dst, scpFunc)
+}
+
+func (c *Communicator) scpDownloadSession(path string, output io.Writer) error {
+	scpFunc := func(w io.Writer, stdoutR *bufio.Reader) error {
+		fmt.Fprint(w, "\x00")
+
+		// read file info
+		fi, err := stdoutR.ReadString('\n')
+		if err != nil {
+			return err
+		}
+
+		if len(fi) < 0 {
+			return fmt.Errorf("empty response from server")
+		}
+
+		switch fi[0] {
+		case '\x01', '\x02':
+			return fmt.Errorf("%s", fi[1:])
+		case 'C':
+		case 'D':
+			return fmt.Errorf("remote file is directory")
+		default:
+			return fmt.Errorf("unexpected server response (%x)", fi[0])
+		}
+
+		var mode string
+		var size int64
+
+		n, err := fmt.Sscanf(fi, "%6s %d ", &mode, &size)
+		if err != nil || n != 2 {
+			return fmt.Errorf("can't parse server response (%s)", fi)
+		}
+		if size < 0 {
+			return fmt.Errorf("negative file size")
+		}
+
+		fmt.Fprint(w, "\x00")
+
+		if _, err := io.CopyN(output, stdoutR, size); err != nil {
+			return err
+		}
+
+		fmt.Fprint(w, "\x00")
+
+		return checkSCPStatus(stdoutR)
+	}
+
+	if !strings.Contains(path, " ") {
+		return c.scpSession("scp -vf "+path, scpFunc)
+	}
+	return c.scpSession("scp -vf "+strconv.Quote(path), scpFunc)
+}
+
+func (c *Communicator) scpSession(scpCommand string, f func(io.Writer, *bufio.Reader) error) error {
+	session, err := c.newSession()
+	if err != nil {
+		return err
+	}
+	defer session.Close()
+
+	// Get a pipe to stdin so that we can send data down
+	stdinW, err := session.StdinPipe()
+	if err != nil {
+		return err
+	}
+
+	// We only want to close once, so we nil w after we close it,
+	// and only close in the defer if it hasn't been closed already.
+	defer func() {
+		if stdinW != nil {
+			stdinW.Close()
+		}
+	}()
+
+	// Get a pipe to stdout so that we can get responses back
+	stdoutPipe, err := session.StdoutPipe()
+	if err != nil {
+		return err
+	}
+	stdoutR := bufio.NewReader(stdoutPipe)
+
+	// Set stderr to a bytes buffer
+	stderr := new(bytes.Buffer)
+	session.Stderr = stderr
+
+	// Start the sink mode on the other side
+	// TODO(mitchellh): There are probably issues with shell escaping the path
+	logger.Debug("starting remote scp process", "command", scpCommand)
+	if err := session.Start(scpCommand); err != nil {
+		return err
+	}
+
+	// Call our callback that executes in the context of SCP. We ignore
+	// EOF errors if they occur because it usually means that SCP prematurely
+	// ended on the other side.
+	logger.Debug("started scp session, beginning transfers")
+	if err := f(stdinW, stdoutR); err != nil && err != io.EOF {
+		return err
+	}
+
+	// Close the stdin, which sends an EOF, and then set w to nil so that
+	// our defer func doesn't close it again since that is unsafe with
+	// the Go SSH package.
+	logger.Debug("scp sessiono complete, closing stdin pipe")
+	stdinW.Close()
+	stdinW = nil
+
+	// Wait for the SCP connection to close, meaning it has consumed all
+	// our data and has completed. Or has errored.
+	logger.Debug("waiting for ssh session to complete")
+	err = session.Wait()
+	if err != nil {
+		if exitErr, ok := err.(*ssh.ExitError); ok {
+			// Otherwise, we have an ExitError, meaning we can just read
+			// the exit status
+			logger.Debug("non-zero exit status", "exitcode", exitErr.ExitStatus())
+			stdoutB, err := ioutil.ReadAll(stdoutR)
+			if err != nil {
+				return err
+			}
+			logger.Debug("scp output", "output", stdoutB)
+
+			// If we exited with status 127, it means SCP isn't available.
+			// Return a more descriptive error for that.
+			if exitErr.ExitStatus() == 127 {
+				return errors.New(
+					"SCP failed to start. This usually means that SCP is not\n" +
+						"properly installed on the remote system.")
+			}
+		}
+
+		return err
+	}
+
+	logger.Debug("scp stderr", "length", stderr.Len(), "content", stderr.String())
+	return nil
+}
+
+// checkSCPStatus checks that a prior command sent to SCP completed
+// successfully. If it did not complete successfully, an error will
+// be returned.
+func checkSCPStatus(r *bufio.Reader) error {
+	code, err := r.ReadByte()
+	if err != nil {
+		return err
+	}
+
+	if code != 0 {
+		// Treat any non-zero (really 1 and 2) as fatal errors
+		message, _, err := r.ReadLine()
+		if err != nil {
+			return fmt.Errorf("Error reading error message: %s", err)
+		}
+
+		return errors.New(string(message))
+	}
+
+	return nil
+}
+
+func scpDownloadFile(dst string, src io.Reader, size int64, mode os.FileMode) error {
+	f, err := os.OpenFile(dst, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, mode)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	if _, err := io.CopyN(f, src, size); err != nil {
+		return err
+	}
+	return nil
+}
+
+func scpUploadFile(dst string, src io.Reader, w io.Writer, r *bufio.Reader, fi *os.FileInfo) error {
+	var mode os.FileMode
+	var size int64
+
+	if fi != nil && (*fi).Mode().IsRegular() {
+		mode = (*fi).Mode().Perm()
+		size = (*fi).Size()
+	} else {
+		// Create a temporary file where we can copy the contents of the src
+		// so that we can determine the length, since SCP is length-prefixed.
+		tf, err := ioutil.TempFile("", "vagrant-upload")
+		if err != nil {
+			return fmt.Errorf("Error creating temporary file for upload: %s", err)
+		}
+		defer os.Remove(tf.Name())
+		defer tf.Close()
+
+		mode = 0644
+
+		logger.Debug("copying input data to temporary file to read length")
+		if _, err := io.Copy(tf, src); err != nil {
+			return fmt.Errorf("Error copying input data into local temporary "+
+				"file. Check that TEMPDIR has enough space. Error: %s", err)
+		}
+
+		// Sync the file so that the contents are definitely on disk, then
+		// read the length of it.
+		if err := tf.Sync(); err != nil {
+			return fmt.Errorf("Error creating temporary file for upload: %s", err)
+		}
+
+		// Seek the file to the beginning so we can re-read all of it
+		if _, err := tf.Seek(0, 0); err != nil {
+			return fmt.Errorf("Error creating temporary file for upload: %s", err)
+		}
+
+		tfi, err := tf.Stat()
+		if err != nil {
+			return fmt.Errorf("Error creating temporary file for upload: %s", err)
+		}
+
+		size = tfi.Size()
+		src = tf
+	}
+
+	// Start the protocol
+	perms := fmt.Sprintf("C%04o", mode)
+	logger.Debug("scp uploading", "path", dst, "perms", perms, "size", size)
+
+	fmt.Fprintln(w, perms, size, dst)
+	if err := checkSCPStatus(r); err != nil {
+		return err
+	}
+
+	if _, err := io.CopyN(w, src, size); err != nil {
+		return err
+	}
+
+	fmt.Fprint(w, "\x00")
+	return checkSCPStatus(r)
+}
+
+func scpUploadDirProtocol(name string, w io.Writer, r *bufio.Reader, f func() error, fi os.FileInfo) error {
+	logger.Debug("scp directory upload", "path", name)
+
+	mode := fi.Mode().Perm()
+
+	perms := fmt.Sprintf("D%04o 0", mode)
+
+	fmt.Fprintln(w, perms, name)
+	err := checkSCPStatus(r)
+	if err != nil {
+		return err
+	}
+
+	if err := f(); err != nil {
+		return err
+	}
+
+	fmt.Fprintln(w, "E")
+	return err
+}
+
+func scpUploadDir(root string, fs []os.FileInfo, w io.Writer, r *bufio.Reader) error {
+	for _, fi := range fs {
+		realPath := filepath.Join(root, fi.Name())
+
+		// Track if this is actually a symlink to a directory. If it is
+		// a symlink to a file we don't do any special behavior because uploading
+		// a file just works. If it is a directory, we need to know so we
+		// treat it as such.
+		isSymlinkToDir := false
+		if fi.Mode()&os.ModeSymlink == os.ModeSymlink {
+			symPath, err := filepath.EvalSymlinks(realPath)
+			if err != nil {
+				return err
+			}
+
+			symFi, err := os.Lstat(symPath)
+			if err != nil {
+				return err
+			}
+
+			isSymlinkToDir = symFi.IsDir()
+		}
+
+		if !fi.IsDir() && !isSymlinkToDir {
+			// It is a regular file (or symlink to a file), just upload it
+			f, err := os.Open(realPath)
+			if err != nil {
+				return err
+			}
+
+			err = func() error {
+				defer f.Close()
+				return scpUploadFile(fi.Name(), f, w, r, &fi)
+			}()
+
+			if err != nil {
+				return err
+			}
+
+			continue
+		}
+
+		// It is a directory, recursively upload
+		err := scpUploadDirProtocol(fi.Name(), w, r, func() error {
+			f, err := os.Open(realPath)
+			if err != nil {
+				return err
+			}
+			defer f.Close()
+
+			entries, err := f.Readdir(-1)
+			if err != nil {
+				return err
+			}
+
+			return scpUploadDir(realPath, entries, w, r)
+		}, fi)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

ext/go-plugin/vagrant/communicator/ssh/communicator_test.go

@@ -0,0 +1,235 @@
+// +build !race
+
+package ssh
+
+import (
+	"bytes"
+	"fmt"
+	"net"
+	"testing"
+	"time"
+
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/communicator"
+	"golang.org/x/crypto/ssh"
+)
+
+// private key for mock server
+const testServerPrivateKey = `-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----`
+
+var serverConfig = &ssh.ServerConfig{
+	PasswordCallback: func(c ssh.ConnMetadata, pass []byte) (*ssh.Permissions, error) {
+		if c.User() == "user" && string(pass) == "pass" {
+			return nil, nil
+		}
+		return nil, fmt.Errorf("password rejected for %q", c.User())
+	},
+}
+
+func init() {
+	// Parse and set the private key of the server, required to accept connections
+	signer, err := ssh.ParsePrivateKey([]byte(testServerPrivateKey))
+	if err != nil {
+		panic("unable to parse private key: " + err.Error())
+	}
+	serverConfig.AddHostKey(signer)
+}
+
+func newMockLineServer(t *testing.T) string {
+	l, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("Unable to listen for connection: %s", err)
+	}
+
+	go func() {
+		defer l.Close()
+		c, err := l.Accept()
+		if err != nil {
+			t.Errorf("Unable to accept incoming connection: %s", err)
+		}
+		defer c.Close()
+		conn, chans, _, err := ssh.NewServerConn(c, serverConfig)
+		if err != nil {
+			t.Logf("Handshaking error: %v", err)
+		}
+		t.Log("Accepted SSH connection")
+		for newChannel := range chans {
+			channel, _, err := newChannel.Accept()
+			if err != nil {
+				t.Errorf("Unable to accept channel.")
+			}
+			t.Log("Accepted channel")
+
+			go func(channelType string) {
+				defer channel.Close()
+				conn.OpenChannel(channelType, nil)
+			}(newChannel.ChannelType())
+		}
+		conn.Close()
+	}()
+
+	return l.Addr().String()
+}
+
+func newMockBrokenServer(t *testing.T) string {
+	l, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatalf("Unable tp listen for connection: %s", err)
+	}
+
+	go func() {
+		defer l.Close()
+		c, err := l.Accept()
+		if err != nil {
+			t.Errorf("Unable to accept incoming connection: %s", err)
+		}
+		defer c.Close()
+		// This should block for a period of time longer than our timeout in
+		// the test case. That way we invoke a failure scenario.
+		t.Log("Block on handshaking for SSH connection")
+		time.Sleep(5 * time.Second)
+	}()
+
+	return l.Addr().String()
+}
+
+func TestCommIsCommunicator(t *testing.T) {
+	var raw interface{}
+	raw = &Communicator{}
+	if _, ok := raw.(communicator.Communicator); !ok {
+		t.Fatalf("Communicator must be a communicator")
+	}
+}
+
+func TestNew_Invalid(t *testing.T) {
+	clientConfig := &ssh.ClientConfig{
+		User: "user",
+		Auth: []ssh.AuthMethod{
+			ssh.Password("i-am-invalid"),
+		},
+		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
+	}
+
+	address := newMockLineServer(t)
+	conn := func() (net.Conn, error) {
+		conn, err := net.Dial("tcp", address)
+		if err != nil {
+			t.Errorf("Unable to accept incoming connection: %v", err)
+		}
+		return conn, err
+	}
+
+	config := &Config{
+		Connection: conn,
+		SSHConfig:  clientConfig,
+	}
+
+	comm, err := New(address, config)
+	if err != nil {
+		t.Fatalf("Failed to setup communicator: %s", err)
+	}
+	err = comm.Connect()
+	if err == nil {
+		t.Fatal("should have had an error connecting")
+	}
+}
+
+func TestStart(t *testing.T) {
+	clientConfig := &ssh.ClientConfig{
+		User: "user",
+		Auth: []ssh.AuthMethod{
+			ssh.Password("pass"),
+		},
+		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
+	}
+
+	address := newMockLineServer(t)
+	conn := func() (net.Conn, error) {
+		conn, err := net.Dial("tcp", address)
+		if err != nil {
+			t.Fatalf("unable to dial to remote side: %s", err)
+		}
+		return conn, err
+	}
+
+	config := &Config{
+		Connection: conn,
+		SSHConfig:  clientConfig,
+	}
+
+	client, err := New(address, config)
+	if err != nil {
+		t.Fatalf("error connecting to SSH: %s", err)
+	}
+
+	cmd := &communicator.Cmd{
+		Command: "echo foo",
+		Stdout:  new(bytes.Buffer),
+	}
+
+	client.Start(cmd)
+}
+
+func TestHandshakeTimeout(t *testing.T) {
+	clientConfig := &ssh.ClientConfig{
+		User: "user",
+		Auth: []ssh.AuthMethod{
+			ssh.Password("pass"),
+		},
+		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
+	}
+
+	address := newMockBrokenServer(t)
+	conn := func() (net.Conn, error) {
+		conn, err := net.Dial("tcp", address)
+		if err != nil {
+			t.Fatalf("unable to dial to remote side: %s", err)
+		}
+		return conn, err
+	}
+
+	config := &Config{
+		Connection:       conn,
+		SSHConfig:        clientConfig,
+		HandshakeTimeout: 50 * time.Millisecond,
+	}
+
+	comm, err := New(address, config)
+	if err != nil {
+		t.Fatalf("Failed to setup communicator: %s", err)
+	}
+	err = comm.Connect()
+	if err != ErrHandshakeTimeout {
+		// Note: there's another error that can come back from this call:
+		//   ssh: handshake failed: EOF
+		// This should appear in cases where the handshake fails because of
+		// malformed (or no) data sent back by the server, but should not happen
+		// in a timeout scenario.
+		t.Fatalf("Expected handshake timeout, got: %s", err)
+	}
+}

ext/go-plugin/vagrant/communicator/ssh/connect.go

@@ -0,0 +1,88 @@
+package ssh
+
+import (
+	"fmt"
+	"net"
+	"time"
+
+	"golang.org/x/crypto/ssh"
+	"golang.org/x/net/proxy"
+)
+
+// ConnectFunc is a convenience method for returning a function
+// that just uses net.Dial to communicate with the remote end that
+// is suitable for use with the SSH communicator configuration.
+func ConnectFunc(network, addr string) func() (net.Conn, error) {
+	return func() (net.Conn, error) {
+		c, err := net.DialTimeout(network, addr, 15*time.Second)
+		if err != nil {
+			return nil, err
+		}
+
+		if tcpConn, ok := c.(*net.TCPConn); ok {
+			tcpConn.SetKeepAlive(true)
+			tcpConn.SetKeepAlivePeriod(5 * time.Second)
+		}
+
+		return c, nil
+	}
+}
+
+// ProxyConnectFunc is a convenience method for returning a function
+// that connects to a host using SOCKS5 proxy
+func ProxyConnectFunc(socksProxy string, socksAuth *proxy.Auth, network, addr string) func() (net.Conn, error) {
+	return func() (net.Conn, error) {
+		// create a socks5 dialer
+		dialer, err := proxy.SOCKS5("tcp", socksProxy, socksAuth, proxy.Direct)
+		if err != nil {
+			return nil, fmt.Errorf("Can't connect to the proxy: %s", err)
+		}
+
+		c, err := dialer.Dial(network, addr)
+		if err != nil {
+			return nil, err
+		}
+
+		return c, nil
+	}
+}
+
+// BastionConnectFunc is a convenience method for returning a function
+// that connects to a host over a bastion connection.
+func BastionConnectFunc(
+	bProto string,
+	bAddr string,
+	bConf *ssh.ClientConfig,
+	proto string,
+	addr string) func() (net.Conn, error) {
+	return func() (net.Conn, error) {
+		// Connect to the bastion
+		bastion, err := ssh.Dial(bProto, bAddr, bConf)
+		if err != nil {
+			return nil, fmt.Errorf("Error connecting to bastion: %s", err)
+		}
+
+		// Connect through to the end host
+		conn, err := bastion.Dial(proto, addr)
+		if err != nil {
+			bastion.Close()
+			return nil, err
+		}
+
+		// Wrap it up so we close both things properly
+		return &bastionConn{
+			Conn:    conn,
+			Bastion: bastion,
+		}, nil
+	}
+}
+
+type bastionConn struct {
+	net.Conn
+	Bastion *ssh.Client
+}
+
+func (c *bastionConn) Close() error {
+	c.Conn.Close()
+	return c.Bastion.Close()
+}

ext/go-plugin/vagrant/communicator/ssh/connection.go

@@ -0,0 +1,30 @@
+package ssh
+
+import (
+	"net"
+	"time"
+)
+
+// timeoutConn wraps a net.Conn, and sets a deadline for every read
+// and write operation.
+type timeoutConn struct {
+	net.Conn
+	ReadTimeout  time.Duration
+	WriteTimeout time.Duration
+}
+
+func (c *timeoutConn) Read(b []byte) (int, error) {
+	err := c.Conn.SetReadDeadline(time.Now().Add(c.ReadTimeout))
+	if err != nil {
+		return 0, err
+	}
+	return c.Conn.Read(b)
+}
+
+func (c *timeoutConn) Write(b []byte) (int, error) {
+	err := c.Conn.SetWriteDeadline(time.Now().Add(c.WriteTimeout))
+	if err != nil {
+		return 0, err
+	}
+	return c.Conn.Write(b)
+}

ext/go-plugin/vagrant/communicator/ssh/password.go

@@ -0,0 +1,25 @@
+package ssh
+
+import (
+	"golang.org/x/crypto/ssh"
+)
+
+// An implementation of ssh.KeyboardInteractiveChallenge that simply sends
+// back the password for all questions. The questions are logged.
+func PasswordKeyboardInteractive(password string) ssh.KeyboardInteractiveChallenge {
+	return func(user, instruction string, questions []string, echos []bool) ([]string, error) {
+		logger.Info("keyboard interactive challenge", "user", user,
+			"instructions", instruction)
+		for i, question := range questions {
+			logger.Info("challenge question", "number", i+1, "question", question)
+		}
+
+		// Just send the password back for all questions
+		answers := make([]string, len(questions))
+		for i := range answers {
+			answers[i] = password
+		}
+
+		return answers, nil
+	}
+}

ext/go-plugin/vagrant/communicator/ssh/password_test.go

@@ -0,0 +1,28 @@
+package ssh
+
+import (
+	"reflect"
+	"testing"
+
+	"golang.org/x/crypto/ssh"
+)
+
+func TestPasswordKeyboardInteractive_Impl(t *testing.T) {
+	var raw interface{}
+	raw = PasswordKeyboardInteractive("foo")
+	if _, ok := raw.(ssh.KeyboardInteractiveChallenge); !ok {
+		t.Fatal("PasswordKeyboardInteractive must implement KeyboardInteractiveChallenge")
+	}
+}
+
+func TestPasswordKeyboardInteractive_Challenge(t *testing.T) {
+	p := PasswordKeyboardInteractive("foo")
+	result, err := p("foo", "bar", []string{"one", "two"}, nil)
+	if err != nil {
+		t.Fatalf("err not nil: %s", err)
+	}
+
+	if !reflect.DeepEqual(result, []string{"foo", "foo"}) {
+		t.Fatalf("invalid password: %#v", result)
+	}
+}

ext/go-plugin/vagrant/communicator/winrm/communicator.go

@@ -0,0 +1,257 @@
+package winrm
+
+import (
+	"encoding/base64"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/communicator"
+	"github.com/masterzen/winrm"
+	"github.com/packer-community/winrmcp/winrmcp"
+)
+
+var logger = vagrant.DefaultLogger().Named("communicator.winrm")
+
+// Communicator represents the WinRM communicator
+type Communicator struct {
+	config   *Config
+	client   *winrm.Client
+	endpoint *winrm.Endpoint
+}
+
+// New creates a new communicator implementation over WinRM.
+func New(config *Config) (*Communicator, error) {
+	endpoint := &winrm.Endpoint{
+		Host:     config.Host,
+		Port:     config.Port,
+		HTTPS:    config.Https,
+		Insecure: config.Insecure,
+
+		/*
+			TODO
+			HTTPS:    connInfo.HTTPS,
+			Insecure: connInfo.Insecure,
+			CACert:   connInfo.CACert,
+		*/
+	}
+
+	// Create the client
+	params := *winrm.DefaultParameters
+
+	if config.TransportDecorator != nil {
+		params.TransportDecorator = config.TransportDecorator
+	}
+
+	params.Timeout = formatDuration(config.Timeout)
+	client, err := winrm.NewClientWithParameters(
+		endpoint, config.Username, config.Password, &params)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Communicator{
+		config:   config,
+		client:   client,
+		endpoint: endpoint,
+	}, nil
+}
+
+func (c *Communicator) Connect() (err error) {
+	// Create the shell to verify the connection
+	logger.Debug("connecting to remote shell")
+	shell, err := c.client.CreateShell()
+	if err != nil {
+		logger.Error("connection failure", "error", err)
+		return
+	}
+	if err = shell.Close(); err != nil {
+		logger.Error("connection close failure", "error", err)
+	}
+	return
+}
+
+// Start implementation of communicator.Communicator interface
+func (c *Communicator) Start(rc *communicator.Cmd) error {
+	shell, err := c.client.CreateShell()
+	if err != nil {
+		return err
+	}
+
+	logger.Info("starting remote command", "commmand", rc.Command)
+
+	rc.Init()
+	cmd, err := shell.Execute(rc.Command)
+	if err != nil {
+		return err
+	}
+
+	go runCommand(shell, cmd, rc)
+	return nil
+}
+
+func runCommand(shell *winrm.Shell, cmd *winrm.Command, rc *communicator.Cmd) {
+	defer shell.Close()
+	var wg sync.WaitGroup
+
+	copyFunc := func(w io.Writer, r io.Reader) {
+		defer wg.Done()
+		io.Copy(w, r)
+	}
+
+	if rc.Stdout != nil && cmd.Stdout != nil {
+		wg.Add(1)
+		go copyFunc(rc.Stdout, cmd.Stdout)
+	} else {
+		logger.Warn("failed to read stdout", "command", rc.Command)
+	}
+
+	if rc.Stderr != nil && cmd.Stderr != nil {
+		wg.Add(1)
+		go copyFunc(rc.Stderr, cmd.Stderr)
+	} else {
+		logger.Warn("failed to read stderr", "command", rc.Command)
+	}
+
+	cmd.Wait()
+	wg.Wait()
+
+	code := cmd.ExitCode()
+	logger.Info("command complete", "exitcode", code, "command", rc.Command)
+	rc.SetExitStatus(code, nil)
+}
+
+// Upload implementation of communicator.Communicator interface
+func (c *Communicator) Upload(path string, input io.Reader, fi *os.FileInfo) error {
+	wcp, err := c.newCopyClient()
+	if err != nil {
+		return fmt.Errorf("Was unable to create winrm client: %s", err)
+	}
+	if strings.HasSuffix(path, `\`) {
+		// path is a directory
+		path += filepath.Base((*fi).Name())
+	}
+	logger.Info("uploading file", "path", path)
+	return wcp.Write(path, input)
+}
+
+// UploadDir implementation of communicator.Communicator interface
+func (c *Communicator) UploadDir(dst string, src string, exclude []string) error {
+	if !strings.HasSuffix(src, "/") {
+		dst = fmt.Sprintf("%s\\%s", dst, filepath.Base(src))
+	}
+	logger.Info("uploading directory", "source", src, "destination", dst)
+	wcp, err := c.newCopyClient()
+	if err != nil {
+		return err
+	}
+	return wcp.Copy(src, dst)
+}
+
+func (c *Communicator) Download(src string, dst io.Writer) error {
+	client, err := c.newWinRMClient()
+	if err != nil {
+		return err
+	}
+
+	encodeScript := `$file=[System.IO.File]::ReadAllBytes("%s"); Write-Output $([System.Convert]::ToBase64String($file))`
+
+	base64DecodePipe := &Base64Pipe{w: dst}
+
+	cmd := winrm.Powershell(fmt.Sprintf(encodeScript, src))
+	_, err = client.Run(cmd, base64DecodePipe, ioutil.Discard)
+
+	return err
+}
+
+func (c *Communicator) DownloadDir(src string, dst string, exclude []string) error {
+	return fmt.Errorf("WinRM doesn't support download dir.")
+}
+
+func (c *Communicator) getClientConfig() *winrmcp.Config {
+	return &winrmcp.Config{
+		Auth: winrmcp.Auth{
+			User:     c.config.Username,
+			Password: c.config.Password,
+		},
+		Https:                 c.config.Https,
+		Insecure:              c.config.Insecure,
+		OperationTimeout:      c.config.Timeout,
+		MaxOperationsPerShell: 15, // lowest common denominator
+		TransportDecorator:    c.config.TransportDecorator,
+	}
+}
+
+func (c *Communicator) newCopyClient() (*winrmcp.Winrmcp, error) {
+	addr := fmt.Sprintf("%s:%d", c.endpoint.Host, c.endpoint.Port)
+	clientConfig := c.getClientConfig()
+	return winrmcp.New(addr, clientConfig)
+}
+
+func (c *Communicator) newWinRMClient() (*winrm.Client, error) {
+	conf := c.getClientConfig()
+
+	// Shamelessly borrowed from the winrmcp client to ensure
+	// that the client is configured using the same defaulting behaviors that
+	// winrmcp uses even we we aren't using winrmcp. This ensures similar
+	// behavior between upload, download, and copy functions. We can't use the
+	// one generated by winrmcp because it isn't exported.
+	var endpoint *winrm.Endpoint
+	endpoint = &winrm.Endpoint{
+		Host:          c.endpoint.Host,
+		Port:          c.endpoint.Port,
+		HTTPS:         conf.Https,
+		Insecure:      conf.Insecure,
+		TLSServerName: conf.TLSServerName,
+		CACert:        conf.CACertBytes,
+		Timeout:       conf.ConnectTimeout,
+	}
+	params := winrm.NewParameters(
+		winrm.DefaultParameters.Timeout,
+		winrm.DefaultParameters.Locale,
+		winrm.DefaultParameters.EnvelopeSize,
+	)
+
+	params.TransportDecorator = conf.TransportDecorator
+	params.Timeout = "PT3M"
+
+	client, err := winrm.NewClientWithParameters(
+		endpoint, conf.Auth.User, conf.Auth.Password, params)
+	return client, err
+}
+
+type Base64Pipe struct {
+	w io.Writer // underlying writer (file, buffer)
+}
+
+func (d *Base64Pipe) ReadFrom(r io.Reader) (int64, error) {
+	b, err := ioutil.ReadAll(r)
+	if err != nil {
+		return 0, err
+	}
+
+	var i int
+	i, err = d.Write(b)
+
+	if err != nil {
+		return 0, err
+	}
+
+	return int64(i), err
+}
+
+func (d *Base64Pipe) Write(p []byte) (int, error) {
+	dst := make([]byte, base64.StdEncoding.DecodedLen(len(p)))
+
+	decodedBytes, err := base64.StdEncoding.Decode(dst, p)
+	if err != nil {
+		return 0, err
+	}
+
+	return d.w.Write(dst[0:decodedBytes])
+}

ext/go-plugin/vagrant/communicator/winrm/communicator_test.go

@@ -0,0 +1,123 @@
+package winrm
+
+import (
+	"bytes"
+	"io"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/dylanmei/winrmtest"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/communicator"
+)
+
+const PAYLOAD = "stuff"
+const BASE64_ENCODED_PAYLOAD = "c3R1ZmY="
+
+func newMockWinRMServer(t *testing.T) *winrmtest.Remote {
+	wrm := winrmtest.NewRemote()
+
+	wrm.CommandFunc(
+		winrmtest.MatchText("echo foo"),
+		func(out, err io.Writer) int {
+			out.Write([]byte("foo"))
+			return 0
+		})
+
+	wrm.CommandFunc(
+		winrmtest.MatchPattern(`^echo c29tZXRoaW5n >> ".*"$`),
+		func(out, err io.Writer) int {
+			return 0
+		})
+
+	wrm.CommandFunc(
+		winrmtest.MatchPattern(`^echo `+BASE64_ENCODED_PAYLOAD+` >> ".*"$`),
+		func(out, err io.Writer) int {
+			return 0
+		})
+
+	wrm.CommandFunc(
+		winrmtest.MatchPattern(`^powershell.exe -EncodedCommand .*$`),
+		func(out, err io.Writer) int {
+			out.Write([]byte(BASE64_ENCODED_PAYLOAD))
+			return 0
+		})
+
+	wrm.CommandFunc(
+		winrmtest.MatchText("powershell"),
+		func(out, err io.Writer) int {
+			return 0
+		})
+	wrm.CommandFunc(
+		winrmtest.MatchText(`powershell -Command "(Get-Item C:/Temp/vagrant.cmd) -is [System.IO.DirectoryInfo]"`),
+		func(out, err io.Writer) int {
+			out.Write([]byte("False"))
+			return 0
+		})
+
+	return wrm
+}
+
+func TestStart(t *testing.T) {
+	wrm := newMockWinRMServer(t)
+	defer wrm.Close()
+
+	c, err := New(&Config{
+		Host:     wrm.Host,
+		Port:     wrm.Port,
+		Username: "user",
+		Password: "pass",
+		Timeout:  30 * time.Second,
+	})
+	if err != nil {
+		t.Fatalf("error creating communicator: %s", err)
+	}
+
+	var cmd communicator.Cmd
+	stdout := new(bytes.Buffer)
+	cmd.Command = "echo foo"
+	cmd.Stdout = stdout
+
+	err = c.Start(&cmd)
+	if err != nil {
+		t.Fatalf("error executing remote command: %s", err)
+	}
+	cmd.Wait()
+
+	if stdout.String() != "foo" {
+		t.Fatalf("bad command response: expected %q, got %q", "foo", stdout.String())
+	}
+}
+
+func TestUpload(t *testing.T) {
+	wrm := newMockWinRMServer(t)
+	defer wrm.Close()
+
+	c, err := New(&Config{
+		Host:     wrm.Host,
+		Port:     wrm.Port,
+		Username: "user",
+		Password: "pass",
+		Timeout:  30 * time.Second,
+	})
+	if err != nil {
+		t.Fatalf("error creating communicator: %s", err)
+	}
+	file := "C:/Temp/vagrant.cmd"
+	err = c.Upload(file, strings.NewReader(PAYLOAD), nil)
+	if err != nil {
+		t.Fatalf("error uploading file: %s", err)
+	}
+
+	dest := new(bytes.Buffer)
+	err = c.Download(file, dest)
+	if err != nil {
+		t.Fatalf("error downloading file: %s", err)
+	}
+	downloadedPayload := dest.String()
+
+	if downloadedPayload != PAYLOAD {
+		t.Fatalf("files are not equal: expected [%s] length: %v, got [%s] length %v", PAYLOAD, len(PAYLOAD), downloadedPayload, len(downloadedPayload))
+	}
+
+}

ext/go-plugin/vagrant/communicator/winrm/config.go

@@ -0,0 +1,19 @@
+package winrm
+
+import (
+	"time"
+
+	"github.com/masterzen/winrm"
+)
+
+// Config is used to configure the WinRM connection
+type Config struct {
+	Host               string
+	Port               int
+	Username           string
+	Password           string
+	Timeout            time.Duration
+	Https              bool
+	Insecure           bool
+	TransportDecorator func() winrm.Transporter
+}

ext/go-plugin/vagrant/communicator/winrm/time.go

@@ -0,0 +1,32 @@
+package winrm
+
+import (
+	"fmt"
+	"time"
+)
+
+// formatDuration formats the given time.Duration into an ISO8601
+// duration string.
+func formatDuration(duration time.Duration) string {
+	// We're not supporting negative durations
+	if duration.Seconds() <= 0 {
+		return "PT0S"
+	}
+
+	h := int(duration.Hours())
+	m := int(duration.Minutes()) - (h * 60)
+	s := int(duration.Seconds()) - (h*3600 + m*60)
+
+	res := "PT"
+	if h > 0 {
+		res = fmt.Sprintf("%s%dH", res, h)
+	}
+	if m > 0 {
+		res = fmt.Sprintf("%s%dM", res, m)
+	}
+	if s > 0 {
+		res = fmt.Sprintf("%s%dS", res, s)
+	}
+
+	return res
+}

ext/go-plugin/vagrant/communicator/winrm/time_test.go

@@ -0,0 +1,36 @@
+package winrm
+
+import (
+	"testing"
+	"time"
+)
+
+func TestFormatDuration(t *testing.T) {
+	// Test complex duration with hours, minutes, seconds
+	d := time.Duration(3701) * time.Second
+	s := formatDuration(d)
+	if s != "PT1H1M41S" {
+		t.Fatalf("bad ISO 8601 duration string: %s", s)
+	}
+
+	// Test only minutes duration
+	d = time.Duration(20) * time.Minute
+	s = formatDuration(d)
+	if s != "PT20M" {
+		t.Fatalf("bad ISO 8601 duration string for 20M: %s", s)
+	}
+
+	// Test only seconds
+	d = time.Duration(1) * time.Second
+	s = formatDuration(d)
+	if s != "PT1S" {
+		t.Fatalf("bad ISO 8601 duration string for 1S: %s", s)
+	}
+
+	// Test negative duration (unsupported)
+	d = time.Duration(-1) * time.Second
+	s = formatDuration(d)
+	if s != "PT0S" {
+		t.Fatalf("bad ISO 8601 duration string for negative: %s", s)
+	}
+}

ext/go-plugin/vagrant/config.go

@@ -0,0 +1,25 @@
+package vagrant
+
+import (
+	"context"
+)
+
+type Config interface {
+	ConfigAttributes() (attrs []string, err error)
+	ConfigLoad(ctx context.Context, data map[string]interface{}) (loaddata map[string]interface{}, err error)
+	ConfigValidate(ctx context.Context, data map[string]interface{}, m *Machine) (errors []string, err error)
+	ConfigFinalize(ctx context.Context, data map[string]interface{}) (finaldata map[string]interface{}, err error)
+}
+
+type NoConfig struct{}
+
+func (c *NoConfig) ConfigAttributes() (a []string, e error) { return }
+func (c *NoConfig) ConfigLoad(context.Context, map[string]interface{}) (d map[string]interface{}, e error) {
+	return
+}
+func (c *NoConfig) ConfigValidate(context.Context, map[string]interface{}, *Machine) (es []string, e error) {
+	return
+}
+func (c *NoConfig) ConfigFinalize(context.Context, map[string]interface{}) (f map[string]interface{}, e error) {
+	return
+}

ext/go-plugin/vagrant/environment.go

@@ -0,0 +1,64 @@
+package vagrant
+
+import (
+	"encoding/json"
+	"io"
+	"os"
+)
+
+type Environment struct {
+	ActiveMachines        map[string]string `json:"active_machines,omitempty"`
+	AliasesPath           string            `json:"aliases_path,omitempty"`
+	BoxesPath             string            `json:"boxes_path,omitempty"`
+	CWD                   string            `json:"cwd,omitempty"`
+	DataDir               string            `json:"data_dir,omitempty"`
+	DefaultPrivateKeyPath string            `json:"default_private_key_path,omitempty"`
+	GemsPath              string            `json:"gems_path,omitempty"`
+	HomePath              string            `json:"home_path,omitempty"`
+	LocalDataPath         string            `json:"local_data_path,omitempty"`
+	MachineNames          []string          `json:"machine_names,omitempty"`
+	PrimaryMachineName    string            `json:"primary_machine_name,omitempty"`
+	RootPath              string            `json:"root_path,omitempty"`
+	TmpPath               string            `json:"tmp_path,omitempty"`
+	VagrantfileName       string            `json:"vagrantfile_name,omitempty"`
+	UI                    Ui                `json:"-"`
+}
+
+func DumpEnvironment(e *Environment) (s string, err error) {
+	DefaultLogger().Debug("dumping environment to serialized data")
+	b, err := json.Marshal(e)
+	if err != nil {
+		DefaultLogger().Error("environment dump failure", "error", err)
+		return
+	}
+	s = string(b)
+	return
+}
+
+func LoadEnvironment(edata string, ios IOServer) (e *Environment, err error) {
+	DefaultLogger().Debug("loading environment from serialized data")
+	e = &Environment{}
+	err = json.Unmarshal([]byte(edata), e)
+	if err != nil {
+		return
+	}
+	var stdout io.Writer
+	var stderr io.Writer
+	if ios == nil {
+		stdout = os.Stdout
+		stderr = os.Stderr
+	} else {
+		stdout = &IOWriter{target: "stdout", srv: ios}
+		stderr = &IOWriter{target: "stderr", srv: ios}
+	}
+	e.UI = &TargetedUi{
+		Target: "vagrant",
+		Ui: &ColoredUi{
+			ErrorColor: UiColorRed,
+			Ui: &BasicUi{
+				Reader:      os.Stdin,
+				Writer:      stdout,
+				ErrorWriter: stderr},
+		}}
+	return
+}

ext/go-plugin/vagrant/environment_test.go

@@ -0,0 +1,63 @@
+package vagrant
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestLoadEnvironment(t *testing.T) {
+	env, err := LoadEnvironment("{}", nil)
+	if err != nil {
+		t.Fatalf("unexpected load error: %s", err)
+	}
+	if env.UI == nil {
+		t.Fatalf("no UI configured for environment")
+	}
+}
+
+func TestBadLoadEnvironment(t *testing.T) {
+	_, err := LoadEnvironment("ack", nil)
+	if err == nil {
+		t.Fatalf("expected load error but none provided")
+	}
+}
+
+func TestLoadEnvironmentUIStdout(t *testing.T) {
+	iosrv := buildio()
+	env, err := LoadEnvironment("{}", iosrv)
+	if err != nil {
+		t.Fatalf("unexpected load error: %s", err)
+	}
+	go func() { env.UI.Info("test string") }()
+	str := <-iosrv.Streams()["stdout"]
+	if !strings.Contains(str, "test string") {
+		t.Fatalf("unexpected output: %s", str)
+	}
+}
+
+func TestLoadEnvironmentUIStderr(t *testing.T) {
+	iosrv := buildio()
+	env, err := LoadEnvironment("{}", iosrv)
+	if err != nil {
+		t.Fatalf("unexpected load error: %s", err)
+	}
+	go func() { env.UI.Error("test string") }()
+	str, err := iosrv.Read("stderr")
+	if !strings.Contains(str, "test string") {
+		t.Fatalf("unexpected output: %s", str)
+	}
+}
+
+func TestDumpEnvironment(t *testing.T) {
+	env, err := LoadEnvironment("{}", nil)
+	if err != nil {
+		t.Fatalf("unexpected load error: %s", err)
+	}
+	d, err := DumpEnvironment(env)
+	if err != nil {
+		t.Fatalf("unexpected dump error: %s", err)
+	}
+	if d != "{}" {
+		t.Fatalf("unexpected dump information: %s", d)
+	}
+}

ext/go-plugin/vagrant/global.go

@@ -0,0 +1,17 @@
+package vagrant
+
+import (
+	hclog "github.com/hashicorp/go-hclog"
+)
+
+var GlobalIOServer *IOServer
+
+var defaultLogger = hclog.Default().Named("vagrant")
+
+func DefaultLogger() hclog.Logger {
+	return defaultLogger
+}
+
+func SetDefaultLogger(l hclog.Logger) {
+	defaultLogger = l
+}

ext/go-plugin/vagrant/io.go

@@ -0,0 +1,53 @@
+package vagrant
+
+import (
+	"errors"
+)
+
+type StreamIO interface {
+	Read(target string) (content string, err error)
+	Write(content, target string) (n int, err error)
+}
+
+type IOServer interface {
+	Streams() map[string]chan (string)
+	StreamIO
+}
+
+type IOSrv struct {
+	Targets map[string]chan (string)
+}
+
+func (i *IOSrv) Streams() map[string]chan (string) {
+	return i.Targets
+}
+
+type IOWriter struct {
+	target string
+	srv    IOServer
+}
+
+func (i *IOWriter) Write(b []byte) (n int, err error) {
+	content := string(b)
+	n, err = i.srv.Write(content, i.target)
+	return
+}
+
+func (i *IOSrv) Read(target string) (content string, err error) {
+	if _, ok := i.Streams()[target]; !ok {
+		err = errors.New("Unknown target defined")
+		return
+	}
+	content = <-i.Streams()[target]
+	return
+}
+
+func (i *IOSrv) Write(content, target string) (n int, err error) {
+	if _, ok := i.Streams()[target]; !ok {
+		err = errors.New("Unknown target defined")
+		return
+	}
+	i.Streams()[target] <- content
+	n = len(content)
+	return
+}

ext/go-plugin/vagrant/io_test.go

@@ -0,0 +1,48 @@
+package vagrant
+
+import (
+	"testing"
+)
+
+func buildio() IOServer {
+	return &IOSrv{
+		Targets: map[string]chan (string){
+			"stdout": make(chan string),
+			"stderr": make(chan string)}}
+}
+
+func TestIOSrvWrite(t *testing.T) {
+	iosrv := buildio()
+	var i int
+	go func() { i, _ = iosrv.Write("test string", "stdout") }()
+	_, _ = iosrv.Read("stdout")
+	if i != len("test string") {
+		t.Fatalf("unexpected write bytes %d != %d",
+			len("test string"), i)
+	}
+}
+
+func TestIOSrvRead(t *testing.T) {
+	iosrv := buildio()
+	go func() { _, _ = iosrv.Write("test string", "stdout") }()
+	r, _ := iosrv.Read("stdout")
+	if r != "test string" {
+		t.Fatalf("unexpected read result: %s", r)
+	}
+}
+
+func TestIOSrvWriteBadTarget(t *testing.T) {
+	iosrv := buildio()
+	_, err := iosrv.Write("test string", "stdno")
+	if err == nil {
+		t.Fatalf("expected error on write")
+	}
+}
+
+func TestIOSrvReadBadTarget(t *testing.T) {
+	iosrv := buildio()
+	_, err := iosrv.Read("stdno")
+	if err == nil {
+		t.Fatalf("expected error on read")
+	}
+}

ext/go-plugin/vagrant/machine.go

@@ -0,0 +1,59 @@
+package vagrant
+
+import (
+	"encoding/json"
+	"io"
+	"os"
+)
+
+type Machine struct {
+	Box             Box                    `json:"box"`
+	Config          map[string]interface{} `json:"config"`
+	DataDir         string                 `json:"data_dir,omitempty"`
+	Env             Environment            `json:"environment"`
+	ID              string                 `json:"id,omitempty"`
+	Name            string                 `json:"name,omitempty"`
+	ProviderConfig  map[string]interface{} `json:"provider_config"`
+	ProviderName    string                 `json:"provider_name,omitempty"`
+	ProviderOptions map[string]string      `json:"provider_options"`
+	UI              Ui                     `json:"-"`
+}
+
+func DumpMachine(m *Machine) (s string, err error) {
+	DefaultLogger().Debug("dumping machine to serialized data")
+	b, err := json.Marshal(m)
+	if err != nil {
+		DefaultLogger().Debug("machine dump failure", "error", err)
+		return
+	}
+	s = string(b)
+	return
+}
+
+func LoadMachine(mdata string, ios IOServer) (m *Machine, err error) {
+	DefaultLogger().Debug("loading machine from serialized data")
+	m = &Machine{}
+	err = json.Unmarshal([]byte(mdata), m)
+	if err != nil {
+		return
+	}
+	var stdout io.Writer
+	var stderr io.Writer
+	if ios == nil {
+		stdout = os.Stdout
+		stderr = os.Stderr
+	} else {
+		stdout = &IOWriter{target: "stdout", srv: ios}
+		stderr = &IOWriter{target: "stderr", srv: ios}
+	}
+	m.UI = &TargetedUi{
+		Target: m.Name,
+		Ui: &ColoredUi{
+			ErrorColor: UiColorRed,
+			Ui: &BasicUi{
+				Reader:      os.Stdin,
+				Writer:      stdout,
+				ErrorWriter: stderr},
+		}}
+	return
+}

ext/go-plugin/vagrant/machine_state.go

@@ -0,0 +1,7 @@
+package vagrant
+
+type MachineState struct {
+	Id        string `json:"id"`
+	ShortDesc string `json:"short_description"`
+	LongDesc  string `json:"long_description"`
+}

ext/go-plugin/vagrant/machine_test.go

@@ -0,0 +1,53 @@
+package vagrant
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestMachineLoad(t *testing.T) {
+	_, err := LoadMachine("{}", nil)
+	if err != nil {
+		t.Fatalf("failed to load machine: %s", err)
+	}
+}
+
+func TestMachineDump(t *testing.T) {
+	m, err := LoadMachine("{}", nil)
+	if err != nil {
+		t.Fatalf("unexpected load error: %s", err)
+	}
+	_, err = DumpMachine(m)
+	if err != nil {
+		t.Fatalf("failed to dump machine: %s", err)
+	}
+}
+
+func TestMachineUI(t *testing.T) {
+	iosrv := buildio()
+	m, err := LoadMachine("{}", iosrv)
+	if err != nil {
+		t.Fatalf("unexpected load error: %s", err)
+	}
+	go func() { m.UI.Info("test string") }()
+	r, _ := iosrv.Read("stdout")
+	if !strings.Contains(r, "test string") {
+		t.Fatalf("unexpected read result: %s", r)
+	}
+}
+
+func TestMachineUINamed(t *testing.T) {
+	iosrv := buildio()
+	m, err := LoadMachine("{\"name\":\"plugintest\"}", iosrv)
+	if err != nil {
+		t.Fatalf("unexpected load error: %s", err)
+	}
+	go func() { m.UI.Info("test string") }()
+	r, _ := iosrv.Read("stdout")
+	if !strings.Contains(r, "test string") {
+		t.Fatalf("unexpected read result: %s", r)
+	}
+	if !strings.Contains(r, "plugintest") {
+		t.Fatalf("output does not contain name: %s", r)
+	}
+}

ext/go-plugin/vagrant/plugin/base.go

@@ -0,0 +1,294 @@
+package plugin
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os"
+	"os/exec"
+	"time"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+
+	hclog "github.com/hashicorp/go-hclog"
+	go_plugin "github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+)
+
+var (
+	Handshake = go_plugin.HandshakeConfig{
+		MagicCookieKey:   "VAGRANT_PLUGIN_MAGIC_COOKIE",
+		MagicCookieValue: "1561a662a76642f98df77ad025aa13a9b16225d93f90475e91090fbe577317ed",
+		ProtocolVersion:  1}
+	ErrPluginShutdown = errors.New("plugin has shutdown")
+)
+
+type RemotePlugin interface {
+	Impl() interface{}
+}
+
+type RemoteConfig struct {
+	Client *go_plugin.Client
+	Config vagrant.Config
+}
+
+func (r *RemoteConfig) Impl() interface{} {
+	return r.Config
+}
+
+type RemoteProvider struct {
+	Client   *go_plugin.Client
+	Provider Provider
+}
+
+func (r *RemoteProvider) Impl() interface{} {
+	return r.Provider
+}
+
+type RemoteGuestCapabilities struct {
+	Client            *go_plugin.Client
+	GuestCapabilities vagrant.GuestCapabilities
+}
+
+func (r *RemoteGuestCapabilities) Impl() interface{} {
+	return r.GuestCapabilities
+}
+
+type RemoteHostCapabilities struct {
+	Client           *go_plugin.Client
+	HostCapabilities vagrant.HostCapabilities
+}
+
+func (r *RemoteHostCapabilities) Impl() interface{} {
+	return r.HostCapabilities
+}
+
+type RemoteProviderCapabilities struct {
+	Client               *go_plugin.Client
+	ProviderCapabilities vagrant.ProviderCapabilities
+}
+
+func (r *RemoteProviderCapabilities) Impl() interface{} {
+	return r.ProviderCapabilities
+}
+
+type RemoteSyncedFolder struct {
+	Client       *go_plugin.Client
+	SyncedFolder vagrant.SyncedFolder
+}
+
+func (r *RemoteSyncedFolder) Impl() interface{} {
+	return r.SyncedFolder
+}
+
+type VagrantPlugin struct {
+	Providers         map[string]*RemoteProvider
+	SyncedFolders     map[string]*RemoteSyncedFolder
+	PluginDirectories []string
+	PluginLookup      func(name, kind string) (p interface{}, err error)
+	Logger            hclog.Logger
+}
+
+func VagrantPluginInit() *VagrantPlugin {
+	v := &VagrantPlugin{
+		PluginDirectories: []string{},
+		Providers:         map[string]*RemoteProvider{},
+		SyncedFolders:     map[string]*RemoteSyncedFolder{},
+		Logger:            vagrant.DefaultLogger().Named("go-plugin")}
+	v.PluginLookup = v.DefaultPluginLookup
+	return v
+}
+
+func (v *VagrantPlugin) DefaultPluginLookup(name, kind string) (p interface{}, err error) {
+	switch kind {
+	case "provider":
+		p = v.Providers[name].Impl()
+	case "synced_folder":
+		p = v.SyncedFolders[name].Impl()
+	default:
+		err = errors.New("invalid plugin type")
+		return
+	}
+	if p == nil {
+		err = errors.New(fmt.Sprintf("Failed to locate %s plugin of type %s", name, kind))
+	}
+	return
+}
+
+func (v *VagrantPlugin) LoadPlugins(pluginPath string) error {
+	for _, p := range v.PluginDirectories {
+		if p == pluginPath {
+			v.Logger.Error("plugin directory path already loaded", "path", pluginPath)
+			return errors.New("plugin directory already loaded")
+		}
+	}
+	v.PluginDirectories = append(v.PluginDirectories, pluginPath)
+	if err := v.LoadProviders(pluginPath); err != nil {
+		return err
+	}
+	if err := v.LoadSyncedFolders(pluginPath); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (v *VagrantPlugin) LoadProviders(pluginPath string) error {
+	providerPaths, err := go_plugin.Discover("*_provider", pluginPath)
+	if err != nil {
+		v.Logger.Error("error during plugin discovery", "type", "provider",
+			"error", err, "path", pluginPath)
+		return err
+	}
+	for _, providerPath := range providerPaths {
+		v.Logger.Info("loading provider plugin", "path", providerPath)
+
+		client := go_plugin.NewClient(&go_plugin.ClientConfig{
+			AllowedProtocols: []go_plugin.Protocol{go_plugin.ProtocolGRPC},
+			Logger:           v.Logger,
+			HandshakeConfig:  Handshake,
+			Cmd:              exec.Command(providerPath),
+			VersionedPlugins: map[int]go_plugin.PluginSet{
+				2: {"provider": &ProviderPlugin{}}}})
+		gclient, err := client.Client()
+		if err != nil {
+			v.Logger.Error("error loading provider client", "error", err, "path", providerPath)
+			return err
+		}
+		raw, err := gclient.Dispense("provider")
+		if err != nil {
+			v.Logger.Error("error loading provider plugin", "error", err, "path", providerPath)
+			return err
+		}
+		prov := raw.(Provider)
+		n := prov.Name()
+		v.Providers[n] = &RemoteProvider{
+			Client:   client,
+			Provider: prov}
+		v.Logger.Info("plugin loaded", "type", "provider", "name", n, "path", providerPath)
+		go v.StreamIO("stdout", prov, n, "provider")
+		go v.StreamIO("stderr", prov, n, "provider")
+	}
+	return nil
+}
+
+func (v *VagrantPlugin) LoadSyncedFolders(pluginPath string) error {
+	folderPaths, err := go_plugin.Discover("*_synced_folder", pluginPath)
+	if err != nil {
+		v.Logger.Error("error during plugin discovery", "type", "synced_folder",
+			"error", err, "path", pluginPath)
+		return err
+	}
+	for _, folderPath := range folderPaths {
+		v.Logger.Info("loading synced_folder plugin", "path", folderPath)
+
+		client := go_plugin.NewClient(&go_plugin.ClientConfig{
+			AllowedProtocols: []go_plugin.Protocol{go_plugin.ProtocolGRPC},
+			Logger:           v.Logger,
+			HandshakeConfig:  Handshake,
+			Cmd:              exec.Command(folderPath),
+			VersionedPlugins: map[int]go_plugin.PluginSet{
+				2: {"synced_folders": &SyncedFolderPlugin{}}}})
+		gclient, err := client.Client()
+		if err != nil {
+			v.Logger.Error("error loading synced_folder client", "error", err, "path", folderPath)
+			return err
+		}
+		raw, err := gclient.Dispense("synced_folder")
+		if err != nil {
+			v.Logger.Error("error loading synced_folder plugin", "error", err, "path", folderPath)
+			return err
+		}
+		fold := raw.(SyncedFolder)
+		n := fold.Name()
+		v.SyncedFolders[n] = &RemoteSyncedFolder{
+			Client:       client,
+			SyncedFolder: fold}
+		v.Logger.Info("plugin loaded", "type", "synced_folder", "name", n, "path", folderPath)
+		go v.StreamIO("stdout", fold, n, "synced_folder")
+		go v.StreamIO("stderr", fold, n, "synced_folder")
+	}
+	return nil
+}
+
+func (v *VagrantPlugin) StreamIO(target string, i vagrant.IOServer, name, kind string) {
+	v.Logger.Info("starting plugin IO streaming", "target", target, "plugin", name, "type", kind)
+	for {
+		str, err := i.Read(target)
+		if err != nil {
+			v.Logger.Error("plugin IO streaming failure", "target", target, "plugin", name,
+				"type", kind, "error", err)
+			break
+		}
+		v.Logger.Debug("received plugin IO content", "target", target, "plugin", name,
+			"type", kind, "content", str)
+		if target == "stdout" {
+			os.Stdout.Write([]byte(str))
+		} else if target == "stderr" {
+			os.Stderr.Write([]byte(str))
+		}
+	}
+	v.Logger.Info("completed plugin IO streaming", "target", target, "plugin", name, "type", kind)
+}
+
+func (v *VagrantPlugin) Kill() {
+	v.Logger.Debug("killing all running plugins")
+	for n, p := range v.Providers {
+		v.Logger.Debug("killing plugin", "name", n, "type", "provider")
+		p.Client.Kill()
+		v.Logger.Info("plugin killed", "name", n, "type", "provider")
+	}
+	for n, p := range v.SyncedFolders {
+		v.Logger.Debug("killing plugin", "name", n, "type", "synced_folder")
+		p.Client.Kill()
+		v.Logger.Info("plugin killed", "name", n, "type", "synced_folder")
+	}
+}
+
+// Helper used for inspect GRPC related errors and providing "correct"
+// error message
+func handleGrpcError(err error, pluginCtx context.Context, reqCtx context.Context) error {
+	// If there was no error then nothing to process
+	if err == nil {
+		return nil
+	}
+
+	// If a request context is provided, check that it
+	// was not canceled or timed out. If no context
+	// provided, stub one for later.
+	if reqCtx != nil {
+		s := status.FromContextError(reqCtx.Err())
+		switch s.Code() {
+		case codes.Canceled:
+			return context.Canceled
+		case codes.DeadlineExceeded:
+			return context.DeadlineExceeded
+		}
+	} else {
+		reqCtx = context.Background()
+	}
+
+	s, ok := status.FromError(err)
+	if ok && (s.Code() == codes.Unavailable || s.Code() == codes.Canceled) {
+		select {
+		case <-pluginCtx.Done():
+			err = ErrPluginShutdown
+		case <-reqCtx.Done():
+			err = reqCtx.Err()
+			select {
+			case <-pluginCtx.Done():
+				err = ErrPluginShutdown
+			default:
+			}
+		case <-time.After(5):
+			return errors.New("exceeded context check timeout - " + err.Error())
+		}
+		return err
+	} else if s != nil && s.Message() != "" {
+		// Extract actual error message received
+		// and create new error
+		return errors.New(s.Message())
+	}
+
+	return err
+}

ext/go-plugin/vagrant/plugin/capabilities.go

@@ -0,0 +1,365 @@
+package plugin
+
+import (
+	"context"
+	"encoding/json"
+
+	"google.golang.org/grpc"
+
+	go_plugin "github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/plugin/proto"
+
+	"github.com/LK4D4/joincontext"
+)
+
+type GuestCapabilities interface {
+	vagrant.GuestCapabilities
+	Meta
+}
+
+type GuestCapabilitiesPlugin struct {
+	go_plugin.NetRPCUnsupportedPlugin
+	Impl GuestCapabilities
+}
+
+func (g *GuestCapabilitiesPlugin) GRPCServer(broker *go_plugin.GRPCBroker, s *grpc.Server) error {
+	g.Impl.Init()
+	vagrant_proto.RegisterGuestCapabilitiesServer(s, &GRPCGuestCapabilitiesServer{
+		Impl: g.Impl,
+		GRPCIOServer: GRPCIOServer{
+			Impl: g.Impl}})
+	return nil
+}
+
+func (g *GuestCapabilitiesPlugin) GRPCClient(ctx context.Context, broker *go_plugin.GRPCBroker, c *grpc.ClientConn) (interface{}, error) {
+	client := vagrant_proto.NewGuestCapabilitiesClient(c)
+	return &GRPCGuestCapabilitiesClient{
+		client:  client,
+		doneCtx: ctx,
+		GRPCIOClient: GRPCIOClient{
+			client:  client,
+			doneCtx: ctx}}, nil
+}
+
+type GRPCGuestCapabilitiesServer struct {
+	GRPCIOServer
+	Impl GuestCapabilities
+}
+
+func (s *GRPCGuestCapabilitiesServer) GuestCapabilities(ctx context.Context, req *vagrant_proto.Empty) (resp *vagrant_proto.SystemCapabilityList, err error) {
+	resp = &vagrant_proto.SystemCapabilityList{}
+	r, err := s.Impl.GuestCapabilities()
+	if err != nil {
+		return
+	}
+	for _, cap := range r {
+		rcap := &vagrant_proto.SystemCapability{Name: cap.Name, Platform: cap.Platform}
+		resp.Capabilities = append(resp.Capabilities, rcap)
+	}
+	return
+}
+
+func (s *GRPCGuestCapabilitiesServer) GuestCapability(ctx context.Context, req *vagrant_proto.GuestCapabilityRequest) (resp *vagrant_proto.GenericResponse, err error) {
+	resp = &vagrant_proto.GenericResponse{}
+	var args interface{}
+	if err = json.Unmarshal([]byte(req.Arguments), &args); err != nil {
+		return
+	}
+	machine, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	cap := &vagrant.SystemCapability{
+		Name:     req.Capability.Name,
+		Platform: req.Capability.Platform}
+	r, err := s.Impl.GuestCapability(ctx, cap, args, machine)
+	result, err := json.Marshal(r)
+	if err != nil {
+		return
+	}
+	resp.Result = string(result)
+	return
+}
+
+type GRPCGuestCapabilitiesClient struct {
+	GRPCCoreClient
+	GRPCIOClient
+	client  vagrant_proto.GuestCapabilitiesClient
+	doneCtx context.Context
+}
+
+func (c *GRPCGuestCapabilitiesClient) GuestCapabilities() (caps []vagrant.SystemCapability, err error) {
+	ctx := context.Background()
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.GuestCapabilities(jctx, &vagrant_proto.Empty{})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	caps = make([]vagrant.SystemCapability, len(resp.Capabilities))
+	for i := 0; i < len(resp.Capabilities); i++ {
+		cap := vagrant.SystemCapability{
+			Name:     resp.Capabilities[i].Name,
+			Platform: resp.Capabilities[i].Platform}
+		caps[i] = cap
+	}
+	return
+}
+
+func (c *GRPCGuestCapabilitiesClient) GuestCapability(ctx context.Context, cap *vagrant.SystemCapability, args interface{}, machine *vagrant.Machine) (result interface{}, err error) {
+	a, err := json.Marshal(args)
+	if err != nil {
+		return
+	}
+	m, err := vagrant.DumpMachine(machine)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.GuestCapability(jctx, &vagrant_proto.GuestCapabilityRequest{
+		Capability: &vagrant_proto.SystemCapability{Name: cap.Name, Platform: cap.Platform},
+		Machine:    m,
+		Arguments:  string(a)})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	err = json.Unmarshal([]byte(resp.Result), &result)
+	return
+}
+
+type HostCapabilities interface {
+	vagrant.HostCapabilities
+	Meta
+}
+
+type HostCapabilitiesPlugin struct {
+	go_plugin.NetRPCUnsupportedPlugin
+	Impl HostCapabilities
+}
+
+func (h *HostCapabilitiesPlugin) GRPCServer(broker *go_plugin.GRPCBroker, s *grpc.Server) error {
+	h.Impl.Init()
+	vagrant_proto.RegisterHostCapabilitiesServer(s, &GRPCHostCapabilitiesServer{
+		Impl: h.Impl,
+		GRPCIOServer: GRPCIOServer{
+			Impl: h.Impl}})
+	return nil
+}
+
+func (h *HostCapabilitiesPlugin) GRPCClient(ctx context.Context, broker *go_plugin.GRPCBroker, c *grpc.ClientConn) (interface{}, error) {
+	client := vagrant_proto.NewHostCapabilitiesClient(c)
+	return &GRPCHostCapabilitiesClient{
+		client:  client,
+		doneCtx: ctx,
+		GRPCIOClient: GRPCIOClient{
+			client:  client,
+			doneCtx: ctx}}, nil
+}
+
+type GRPCHostCapabilitiesServer struct {
+	GRPCIOServer
+	Impl HostCapabilities
+}
+
+func (s *GRPCHostCapabilitiesServer) HostCapabilities(ctx context.Context, req *vagrant_proto.Empty) (resp *vagrant_proto.SystemCapabilityList, err error) {
+	resp = &vagrant_proto.SystemCapabilityList{}
+	r, err := s.Impl.HostCapabilities()
+	if err != nil {
+		return
+	}
+	for _, cap := range r {
+		rcap := &vagrant_proto.SystemCapability{Name: cap.Name, Platform: cap.Platform}
+		resp.Capabilities = append(resp.Capabilities, rcap)
+	}
+	return
+}
+
+func (s *GRPCHostCapabilitiesServer) HostCapability(ctx context.Context, req *vagrant_proto.HostCapabilityRequest) (resp *vagrant_proto.GenericResponse, err error) {
+	resp = &vagrant_proto.GenericResponse{}
+	var args interface{}
+	if err = json.Unmarshal([]byte(req.Arguments), &args); err != nil {
+		return
+	}
+	env, err := vagrant.LoadEnvironment(req.Environment, s.Impl)
+	if err != nil {
+		return
+	}
+	cap := &vagrant.SystemCapability{
+		Name:     req.Capability.Name,
+		Platform: req.Capability.Platform}
+
+	r, err := s.Impl.HostCapability(ctx, cap, args, env)
+	result, err := json.Marshal(r)
+	if err != nil {
+		return
+	}
+	resp.Result = string(result)
+	return
+}
+
+type GRPCHostCapabilitiesClient struct {
+	GRPCCoreClient
+	GRPCIOClient
+	client  vagrant_proto.HostCapabilitiesClient
+	doneCtx context.Context
+}
+
+func (c *GRPCHostCapabilitiesClient) HostCapabilities() (caps []vagrant.SystemCapability, err error) {
+	ctx := context.Background()
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.HostCapabilities(jctx, &vagrant_proto.Empty{})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	caps = make([]vagrant.SystemCapability, len(resp.Capabilities))
+	for i := 0; i < len(resp.Capabilities); i++ {
+		cap := vagrant.SystemCapability{
+			Name:     resp.Capabilities[i].Name,
+			Platform: resp.Capabilities[i].Platform}
+		caps[i] = cap
+	}
+	return
+}
+
+func (c *GRPCHostCapabilitiesClient) HostCapability(ctx context.Context, cap *vagrant.SystemCapability, args interface{}, env *vagrant.Environment) (result interface{}, err error) {
+	a, err := json.Marshal(args)
+	if err != nil {
+		return
+	}
+	e, err := vagrant.DumpEnvironment(env)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.HostCapability(jctx, &vagrant_proto.HostCapabilityRequest{
+		Capability: &vagrant_proto.SystemCapability{
+			Name:     cap.Name,
+			Platform: cap.Platform},
+		Environment: e,
+		Arguments:   string(a)})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	err = json.Unmarshal([]byte(resp.Result), &result)
+	return
+}
+
+type ProviderCapabilities interface {
+	vagrant.ProviderCapabilities
+	Meta
+}
+
+type ProviderCapabilitiesPlugin struct {
+	go_plugin.NetRPCUnsupportedPlugin
+	Impl ProviderCapabilities
+}
+
+func (p *ProviderCapabilitiesPlugin) GRPCServer(broker *go_plugin.GRPCBroker, s *grpc.Server) error {
+	p.Impl.Init()
+	vagrant_proto.RegisterProviderCapabilitiesServer(s, &GRPCProviderCapabilitiesServer{
+		Impl: p.Impl,
+		GRPCIOServer: GRPCIOServer{
+			Impl: p.Impl}})
+	return nil
+}
+
+func (p *ProviderCapabilitiesPlugin) GRPCClient(ctx context.Context, broker *go_plugin.GRPCBroker, c *grpc.ClientConn) (interface{}, error) {
+	client := vagrant_proto.NewProviderCapabilitiesClient(c)
+	return &GRPCProviderCapabilitiesClient{
+		client:  client,
+		doneCtx: ctx,
+		GRPCIOClient: GRPCIOClient{
+			client:  client,
+			doneCtx: ctx}}, nil
+}
+
+type GRPCProviderCapabilitiesServer struct {
+	GRPCIOServer
+	Impl ProviderCapabilities
+}
+
+func (s *GRPCProviderCapabilitiesServer) ProviderCapabilities(ctx context.Context, req *vagrant_proto.Empty) (resp *vagrant_proto.ProviderCapabilityList, err error) {
+	resp = &vagrant_proto.ProviderCapabilityList{}
+	r, err := s.Impl.ProviderCapabilities()
+	if err != nil {
+		return
+	}
+	for _, cap := range r {
+		rcap := &vagrant_proto.ProviderCapability{Name: cap.Name, Provider: cap.Provider}
+		resp.Capabilities = append(resp.Capabilities, rcap)
+	}
+	return
+}
+
+func (s *GRPCProviderCapabilitiesServer) ProviderCapability(ctx context.Context, req *vagrant_proto.ProviderCapabilityRequest) (resp *vagrant_proto.GenericResponse, err error) {
+	resp = &vagrant_proto.GenericResponse{}
+	var args interface{}
+	if err = json.Unmarshal([]byte(req.Arguments), &args); err != nil {
+		return
+	}
+	m, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	cap := &vagrant.ProviderCapability{
+		Name:     req.Capability.Name,
+		Provider: req.Capability.Provider}
+
+	r, err := s.Impl.ProviderCapability(ctx, cap, args, m)
+	if err != nil {
+		return
+	}
+	result, err := json.Marshal(r)
+	if err != nil {
+		return
+	}
+	resp.Result = string(result)
+	return
+}
+
+type GRPCProviderCapabilitiesClient struct {
+	GRPCCoreClient
+	GRPCIOClient
+	client  vagrant_proto.ProviderCapabilitiesClient
+	doneCtx context.Context
+}
+
+func (c *GRPCProviderCapabilitiesClient) ProviderCapabilities() (caps []vagrant.ProviderCapability, err error) {
+	ctx := context.Background()
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.ProviderCapabilities(jctx, &vagrant_proto.Empty{})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	caps = make([]vagrant.ProviderCapability, len(resp.Capabilities))
+	for i := 0; i < len(resp.Capabilities); i++ {
+		cap := vagrant.ProviderCapability{
+			Name:     resp.Capabilities[i].Name,
+			Provider: resp.Capabilities[i].Provider}
+		caps[i] = cap
+	}
+	return
+}
+
+func (c *GRPCProviderCapabilitiesClient) ProviderCapability(ctx context.Context, cap *vagrant.ProviderCapability, args interface{}, machine *vagrant.Machine) (result interface{}, err error) {
+	a, err := json.Marshal(args)
+	if err != nil {
+		return
+	}
+	m, err := vagrant.DumpMachine(machine)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.ProviderCapability(jctx, &vagrant_proto.ProviderCapabilityRequest{
+		Capability: &vagrant_proto.ProviderCapability{
+			Name:     cap.Name,
+			Provider: cap.Provider},
+		Machine:   m,
+		Arguments: string(a)})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	err = json.Unmarshal([]byte(resp.Result), &result)
+	return
+}

ext/go-plugin/vagrant/plugin/capabilities_test.go

@@ -0,0 +1,499 @@
+package plugin
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+)
+
+func TestCapabilities_GuestCapabilities(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &GuestCapabilitiesPlugin{Impl: &MockGuestCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(GuestCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+	resp, err := impl.GuestCapabilities()
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if len(resp) != 1 {
+		t.Fatalf("length %d != 1", len(resp))
+	}
+	if resp[0].Name != "test_cap" {
+		t.Errorf("name - %s != test_cap", resp[0].Name)
+	}
+	if resp[0].Platform != "testOS" {
+		t.Errorf("platform - %s != testOS", resp[0].Platform)
+	}
+}
+
+func TestCapabilities_GuestCapability(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &GuestCapabilitiesPlugin{Impl: &MockGuestCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(GuestCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.SystemCapability{
+		Name:     "test_cap",
+		Platform: "TestOS"}
+	m := &vagrant.Machine{}
+	args := []string{"test_value", "next_test_value"}
+
+	resp, err := impl.GuestCapability(context.Background(), cap, args, m)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	result, ok := resp.([]interface{})
+	if !ok {
+		t.Fatalf("bad %#v", result)
+	}
+	if result[0] != "test_cap" {
+		t.Errorf("%s != test_cap", result[0])
+	}
+	if result[1] != "test_value" {
+		t.Errorf("%s != test_value", result[1])
+	}
+}
+
+func TestCapabilities_GuestCapability_noargs(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &GuestCapabilitiesPlugin{Impl: &MockGuestCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(GuestCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.SystemCapability{
+		Name:     "test_cap",
+		Platform: "TestOS"}
+	m := &vagrant.Machine{}
+	var args interface{}
+	args = nil
+
+	resp, err := impl.GuestCapability(context.Background(), cap, args, m)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	result, ok := resp.([]interface{})
+	if !ok {
+		t.Fatalf("bad %#v", result)
+	}
+	if result[0] != "test_cap" {
+		t.Errorf("%s != test_cap", result[0])
+	}
+}
+
+func TestCapabilities_GuestCapability_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &GuestCapabilitiesPlugin{Impl: &MockGuestCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(GuestCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.SystemCapability{
+		Name:     "test_cap",
+		Platform: "TestOS"}
+	m := &vagrant.Machine{}
+	args := []string{"pause", "test_value", "next_test_value"}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.GuestCapability(ctx, cap, args, m)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestCapabilities_GuestCapability_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &GuestCapabilitiesPlugin{Impl: &MockGuestCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(GuestCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.SystemCapability{
+		Name:     "test_cap",
+		Platform: "TestOS"}
+	m := &vagrant.Machine{}
+	args := []string{"pause", "test_value", "next_test_value"}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.GuestCapability(ctx, cap, args, m)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestCapabilities_HostCapabilities(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &HostCapabilitiesPlugin{Impl: &MockHostCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(HostCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+	resp, err := impl.HostCapabilities()
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if len(resp) != 1 {
+		t.Fatalf("length %d != 1", len(resp))
+	}
+	if resp[0].Name != "test_cap" {
+		t.Errorf("name - %s != test_cap", resp[0].Name)
+	}
+	if resp[0].Platform != "testOS" {
+		t.Errorf("platform - %s != testOS", resp[0].Platform)
+	}
+}
+
+func TestCapabilities_HostCapability(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &HostCapabilitiesPlugin{Impl: &MockHostCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(HostCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.SystemCapability{
+		Name:     "test_cap",
+		Platform: "TestOS"}
+	e := &vagrant.Environment{}
+	args := []string{"test_value", "next_test_value"}
+
+	resp, err := impl.HostCapability(context.Background(), cap, args, e)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	result, ok := resp.([]interface{})
+	if !ok {
+		t.Fatalf("bad %#v", result)
+	}
+	if result[0] != "test_cap" {
+		t.Errorf("%s != test_cap", result[0])
+	}
+	if result[1] != "test_value" {
+		t.Errorf("%s != test_value", result[1])
+	}
+}
+
+func TestCapabilities_HostCapability_noargs(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &HostCapabilitiesPlugin{Impl: &MockHostCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(HostCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.SystemCapability{
+		Name:     "test_cap",
+		Platform: "TestOS"}
+	e := &vagrant.Environment{}
+	var args interface{}
+	args = nil
+
+	resp, err := impl.HostCapability(context.Background(), cap, args, e)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	result, ok := resp.([]interface{})
+	if !ok {
+		t.Fatalf("bad %#v", result)
+	}
+	if result[0] != "test_cap" {
+		t.Errorf("%s != test_cap", result[0])
+	}
+}
+
+func TestCapabilities_HostCapability_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &HostCapabilitiesPlugin{Impl: &MockHostCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(HostCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.SystemCapability{
+		Name:     "test_cap",
+		Platform: "TestOS"}
+	e := &vagrant.Environment{}
+	args := []string{"pause", "test_value", "next_test_value"}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.HostCapability(ctx, cap, args, e)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestCapabilities_HostCapability_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &HostCapabilitiesPlugin{Impl: &MockHostCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(HostCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.SystemCapability{
+		Name:     "test_cap",
+		Platform: "TestOS"}
+	e := &vagrant.Environment{}
+	args := []string{"pause", "test_value", "next_test_value"}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.HostCapability(ctx, cap, args, e)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestCapabilities_ProviderCapabilities(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &ProviderCapabilitiesPlugin{Impl: &MockProviderCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(ProviderCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+	resp, err := impl.ProviderCapabilities()
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if len(resp) != 1 {
+		t.Fatalf("length %d != 1", len(resp))
+	}
+	if resp[0].Name != "test_cap" {
+		t.Errorf("name - %s != test_cap", resp[0].Name)
+	}
+	if resp[0].Provider != "testProvider" {
+		t.Errorf("provider - %s != testProvdier", resp[0].Provider)
+	}
+}
+
+func TestCapabilities_ProviderCapability(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &ProviderCapabilitiesPlugin{Impl: &MockProviderCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(ProviderCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.ProviderCapability{
+		Name:     "test_cap",
+		Provider: "test_provider"}
+	m := &vagrant.Machine{}
+	args := []string{"test_value", "next_test_value"}
+
+	resp, err := impl.ProviderCapability(context.Background(), cap, args, m)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	result, ok := resp.([]interface{})
+	if !ok {
+		t.Fatalf("bad %#v", result)
+	}
+	if result[0] != "test_cap" {
+		t.Errorf("%s != test_cap", result[0])
+	}
+	if result[1] != "test_value" {
+		t.Errorf("%s != test_value", result[1])
+	}
+}
+
+func TestCapabilities_ProviderCapability_noargs(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &ProviderCapabilitiesPlugin{Impl: &MockProviderCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(ProviderCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.ProviderCapability{
+		Name:     "test_cap",
+		Provider: "test_provider"}
+	m := &vagrant.Machine{}
+	var args interface{}
+	args = nil
+
+	resp, err := impl.ProviderCapability(context.Background(), cap, args, m)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	result, ok := resp.([]interface{})
+	if !ok {
+		t.Fatalf("bad %#v", result)
+	}
+	if result[0] != "test_cap" {
+		t.Errorf("%s != test_cap", result[0])
+	}
+}
+
+func TestCapabilities_ProviderCapability_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &ProviderCapabilitiesPlugin{Impl: &MockProviderCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(ProviderCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.ProviderCapability{
+		Name:     "test_cap",
+		Provider: "test_provider"}
+	m := &vagrant.Machine{}
+	args := []string{"pause", "test_value", "next_test_value"}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.ProviderCapability(ctx, cap, args, m)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestCapabilities_ProviderCapability_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"caps": &ProviderCapabilitiesPlugin{Impl: &MockProviderCapabilities{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("caps")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(ProviderCapabilities)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	cap := &vagrant.ProviderCapability{
+		Name:     "test_cap",
+		Provider: "test_provider"}
+	m := &vagrant.Machine{}
+	args := []string{"pause", "test_value", "next_test_value"}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.ProviderCapability(ctx, cap, args, m)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}

ext/go-plugin/vagrant/plugin/config.go

@@ -0,0 +1,175 @@
+package plugin
+
+import (
+	"context"
+	"encoding/json"
+
+	"google.golang.org/grpc"
+
+	go_plugin "github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/plugin/proto"
+
+	"github.com/LK4D4/joincontext"
+)
+
+type Config interface {
+	vagrant.Config
+	Meta
+}
+
+type ConfigPlugin struct {
+	go_plugin.NetRPCUnsupportedPlugin
+	Impl Config
+}
+
+func (c *ConfigPlugin) GRPCServer(broker *go_plugin.GRPCBroker, s *grpc.Server) error {
+	c.Impl.Init()
+	vagrant_proto.RegisterConfigServer(s, &GRPCConfigServer{
+		Impl: c.Impl,
+		GRPCIOServer: GRPCIOServer{
+			Impl: c.Impl}})
+	return nil
+}
+
+func (c *ConfigPlugin) GRPCClient(ctx context.Context, broker *go_plugin.GRPCBroker, con *grpc.ClientConn) (interface{}, error) {
+	client := vagrant_proto.NewConfigClient(con)
+	return &GRPCConfigClient{
+		client:  client,
+		doneCtx: ctx,
+		GRPCIOClient: GRPCIOClient{
+			client:  client,
+			doneCtx: ctx}}, nil
+}
+
+type GRPCConfigServer struct {
+	GRPCIOServer
+	Impl Config
+}
+
+func (s *GRPCConfigServer) ConfigAttributes(ctx context.Context, req *vagrant_proto.Empty) (resp *vagrant_proto.ListResponse, err error) {
+	resp = &vagrant_proto.ListResponse{}
+	resp.Items, err = s.Impl.ConfigAttributes()
+	return
+}
+
+func (s *GRPCConfigServer) ConfigLoad(ctx context.Context, req *vagrant_proto.Configuration) (resp *vagrant_proto.Configuration, err error) {
+	resp = &vagrant_proto.Configuration{}
+	var data map[string]interface{}
+	err = json.Unmarshal([]byte(req.Data), &data)
+	if err != nil {
+		return
+	}
+	r, err := s.Impl.ConfigLoad(ctx, data)
+	if err != nil {
+		return
+	}
+	mdata, err := json.Marshal(r)
+	if err != nil {
+		return
+	}
+	resp.Data = string(mdata)
+	return
+}
+
+func (s *GRPCConfigServer) ConfigValidate(ctx context.Context, req *vagrant_proto.Configuration) (resp *vagrant_proto.ListResponse, err error) {
+	resp = &vagrant_proto.ListResponse{}
+	var data map[string]interface{}
+	err = json.Unmarshal([]byte(req.Data), &data)
+	if err != nil {
+		return
+	}
+	m, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	resp.Items, err = s.Impl.ConfigValidate(ctx, data, m)
+	return
+}
+
+func (s *GRPCConfigServer) ConfigFinalize(ctx context.Context, req *vagrant_proto.Configuration) (resp *vagrant_proto.Configuration, err error) {
+	resp = &vagrant_proto.Configuration{}
+	var data map[string]interface{}
+	err = json.Unmarshal([]byte(req.Data), &data)
+	if err != nil {
+		return
+	}
+	r, err := s.Impl.ConfigFinalize(ctx, data)
+	if err != nil {
+		return
+	}
+	mdata, err := json.Marshal(r)
+	if err != nil {
+		return
+	}
+	resp.Data = string(mdata)
+	return
+}
+
+type GRPCConfigClient struct {
+	GRPCCoreClient
+	GRPCIOClient
+	client  vagrant_proto.ConfigClient
+	doneCtx context.Context
+}
+
+func (c *GRPCConfigClient) ConfigAttributes() (attrs []string, err error) {
+	ctx := context.Background()
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.ConfigAttributes(jctx, &vagrant_proto.Empty{})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, nil)
+	}
+	attrs = resp.Items
+	return
+}
+
+func (c *GRPCConfigClient) ConfigLoad(ctx context.Context, data map[string]interface{}) (loaddata map[string]interface{}, err error) {
+	mdata, err := json.Marshal(data)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.ConfigLoad(jctx, &vagrant_proto.Configuration{
+		Data: string(mdata)})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	err = json.Unmarshal([]byte(resp.Data), &loaddata)
+	return
+}
+
+func (c *GRPCConfigClient) ConfigValidate(ctx context.Context, data map[string]interface{}, m *vagrant.Machine) (errs []string, err error) {
+	machData, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	mdata, err := json.Marshal(data)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.ConfigValidate(jctx, &vagrant_proto.Configuration{
+		Data:    string(mdata),
+		Machine: machData})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	errs = resp.Items
+	return
+}
+
+func (c *GRPCConfigClient) ConfigFinalize(ctx context.Context, data map[string]interface{}) (finaldata map[string]interface{}, err error) {
+	mdata, err := json.Marshal(data)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.ConfigFinalize(jctx, &vagrant_proto.Configuration{
+		Data: string(mdata)})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	err = json.Unmarshal([]byte(resp.Data), &finaldata)
+	return
+}

ext/go-plugin/vagrant/plugin/config_test.go

@@ -0,0 +1,246 @@
+package plugin
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+)
+
+func TestConfigPlugin_Attributes(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"configs": &ConfigPlugin{Impl: &MockConfig{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("configs")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Config)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	resp, err := impl.ConfigAttributes()
+	if err != nil {
+		t.Fatalf("bad resp %s", err)
+	}
+	if resp[0] != "fubar" {
+		t.Errorf("%s != fubar", resp[0])
+	}
+	if resp[1] != "foobar" {
+		t.Errorf("%s != foobar", resp[1])
+	}
+}
+
+func TestConfigPlugin_Load(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"configs": &ConfigPlugin{Impl: &MockConfig{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("configs")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Config)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	data := map[string]interface{}{}
+	var resp map[string]interface{}
+	resp, err = impl.ConfigLoad(context.Background(), data)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if _, ok := resp["test_key"]; !ok {
+		t.Fatalf("bad resp content %#v", resp)
+	}
+	v := resp["test_key"].(string)
+	if v != "test_val" {
+		t.Errorf("%s != test_val", v)
+	}
+}
+
+func TestConfigPlugin_Load_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"configs": &ConfigPlugin{Impl: &MockConfig{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("configs")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Config)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	data := map[string]interface{}{"pause": true}
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.ConfigLoad(ctx, data)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestConfigPlugin_Load_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"configs": &ConfigPlugin{Impl: &MockConfig{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("configs")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Config)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	data := map[string]interface{}{"pause": true}
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.ConfigLoad(ctx, data)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestConfigPlugin_Validate(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"configs": &ConfigPlugin{Impl: &MockConfig{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("configs")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Config)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	data := map[string]interface{}{}
+	machine := &vagrant.Machine{}
+
+	resp, err := impl.ConfigValidate(context.Background(), data, machine)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if len(resp) != 1 {
+		t.Fatalf("bad size %d != 1", len(resp))
+	}
+	if resp[0] != "test error" {
+		t.Errorf("%s != test error", resp[0])
+	}
+}
+
+func TestConfigPlugin_Validate_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"configs": &ConfigPlugin{Impl: &MockConfig{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("configs")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Config)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	data := map[string]interface{}{"pause": true}
+	machine := &vagrant.Machine{}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.ConfigValidate(ctx, data, machine)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestConfigPlugin_Finalize(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"configs": &ConfigPlugin{Impl: &MockConfig{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("configs")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Config)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	data := map[string]interface{}{
+		"test_key":  "test_val",
+		"other_key": "other_val"}
+
+	resp, err := impl.ConfigFinalize(context.Background(), data)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if _, ok := resp["test_key"]; !ok {
+		t.Fatalf("bad resp content %#v", resp)
+	}
+	v := resp["test_key"].(string)
+	if v != "test_val-updated" {
+		t.Errorf("%s != test_val-updated", v)
+	}
+	v = resp["other_key"].(string)
+	if v != "other_val-updated" {
+		t.Errorf("%s != other_val-updated", v)
+	}
+}
+
+func TestConfigPlugin_Finalize_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"configs": &ConfigPlugin{Impl: &MockConfig{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("configs")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Config)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	data := map[string]interface{}{
+		"pause":     true,
+		"test_key":  "test_val",
+		"other_key": "other_val"}
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.ConfigFinalize(ctx, data)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}

ext/go-plugin/vagrant/plugin/io.go

@@ -0,0 +1,84 @@
+package plugin
+
+import (
+	"context"
+
+	"google.golang.org/grpc"
+
+	go_plugin "github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/plugin/proto"
+
+	"github.com/LK4D4/joincontext"
+)
+
+type IO interface {
+	vagrant.StreamIO
+}
+
+type IOPlugin struct {
+	go_plugin.NetRPCUnsupportedPlugin
+	Impl vagrant.StreamIO
+}
+
+type GRPCIOServer struct {
+	Impl vagrant.StreamIO
+}
+
+func (s *GRPCIOServer) Read(ctx context.Context, req *vagrant_proto.Identifier) (r *vagrant_proto.Content, err error) {
+	r = &vagrant_proto.Content{}
+	r.Value, err = s.Impl.Read(req.Name)
+	return
+}
+
+func (s *GRPCIOServer) Write(ctx context.Context, req *vagrant_proto.Content) (r *vagrant_proto.WriteResponse, err error) {
+	r = &vagrant_proto.WriteResponse{}
+	bytes := 0
+	bytes, err = s.Impl.Write(req.Value, req.Target)
+	if err != nil {
+		return
+	}
+	r.Length = int32(bytes)
+	return
+}
+
+type GRPCIOClient struct {
+	client  vagrant_proto.IOClient
+	doneCtx context.Context
+}
+
+func (c *GRPCIOClient) Read(target string) (content string, err error) {
+	ctx := context.Background()
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.Read(jctx, &vagrant_proto.Identifier{
+		Name: target})
+	if err != nil {
+		return content, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	content = resp.Value
+	return
+}
+
+func (c *GRPCIOClient) Write(content, target string) (length int, err error) {
+	ctx := context.Background()
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.Write(jctx, &vagrant_proto.Content{
+		Value:  content,
+		Target: target})
+	if err != nil {
+		return length, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	length = int(resp.Length)
+	return
+}
+
+func (i *IOPlugin) GRPCServer(broker *go_plugin.GRPCBroker, s *grpc.Server) error {
+	vagrant_proto.RegisterIOServer(s, &GRPCIOServer{Impl: i.Impl})
+	return nil
+}
+
+func (i *IOPlugin) GRPCClient(ctx context.Context, broker *go_plugin.GRPCBroker, c *grpc.ClientConn) (interface{}, error) {
+	return &GRPCIOClient{
+		client:  vagrant_proto.NewIOClient(c),
+		doneCtx: ctx}, nil
+}

ext/go-plugin/vagrant/plugin/io_test.go

@@ -0,0 +1,89 @@
+package plugin
+
+import (
+	"testing"
+
+	"github.com/hashicorp/go-plugin"
+)
+
+type MockIO struct {
+	Core
+}
+
+func TestIO_ReadWrite(t *testing.T) {
+	ioplugin := &MockIO{}
+	ioplugin.Init()
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"io": &IOPlugin{Impl: ioplugin}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("io")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(IO)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+	go func() {
+		length, err := impl.Write("test_message", "stdout")
+		if err != nil {
+			t.Fatalf("bad write: %s", err)
+		}
+		if length != len("test_message") {
+			t.Fatalf("bad length %d != %d", length, len("test_message"))
+		}
+	}()
+	resp, err := impl.Read("stdout")
+	if err != nil {
+		t.Fatalf("bad read: %s", err)
+	}
+	if resp != "test_message" {
+		t.Errorf("%s != test_message", resp)
+	}
+}
+
+func TestIO_Write_bad(t *testing.T) {
+	ioplugin := &MockIO{}
+	ioplugin.Init()
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"io": &IOPlugin{Impl: ioplugin}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("io")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(IO)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+	_, err = impl.Write("test_message", "bad-target")
+	if err == nil {
+		t.Fatalf("illegal write")
+	}
+}
+
+func TestIO_Read_bad(t *testing.T) {
+	ioplugin := &MockIO{}
+	ioplugin.Init()
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"io": &IOPlugin{Impl: ioplugin}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("io")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(IO)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+	_, err = impl.Read("bad-target")
+	if err == nil {
+		t.Fatalf("illegal read")
+	}
+}

ext/go-plugin/vagrant/plugin/meta.go

@@ -0,0 +1,39 @@
+package plugin
+
+import (
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+)
+
+type Meta interface {
+	Init()
+	vagrant.IOServer
+}
+
+type GRPCCoreClient struct{}
+
+func (c *GRPCCoreClient) Init()                                 {}
+func (c *GRPCCoreClient) Streams() (s map[string]chan (string)) { return }
+
+type Core struct {
+	vagrant.IOServer
+	io vagrant.StreamIO
+}
+
+func (c *Core) Init() {
+	if c.io == nil {
+		c.io = &vagrant.IOSrv{
+			map[string]chan (string){
+				"stdout": make(chan string),
+				"stderr": make(chan string),
+			},
+		}
+	}
+}
+
+func (c *Core) Read(target string) (string, error) {
+	return c.io.Read(target)
+}
+
+func (c *Core) Write(content, target string) (int, error) {
+	return c.io.Write(content, target)
+}

ext/go-plugin/vagrant/plugin/mocks.go

@@ -0,0 +1,300 @@
+package plugin
+
+import (
+	"context"
+	"errors"
+	"time"
+
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+)
+
+type MockGuestCapabilities struct{ Core }
+
+func (g *MockGuestCapabilities) GuestCapabilities() (caps []vagrant.SystemCapability, err error) {
+	caps = []vagrant.SystemCapability{
+		vagrant.SystemCapability{Name: "test_cap", Platform: "testOS"}}
+	return
+}
+
+func (g *MockGuestCapabilities) GuestCapability(ctx context.Context, cap *vagrant.SystemCapability, args interface{}, m *vagrant.Machine) (result interface{}, err error) {
+	if args != nil {
+		arguments := args.([]interface{})
+		if arguments[0] == "pause" {
+			time.Sleep(1 * time.Second)
+		}
+		if len(arguments) > 0 {
+			result = []string{
+				cap.Name,
+				arguments[0].(string)}
+			return
+		}
+	}
+	result = []string{cap.Name}
+	return
+}
+
+type MockHostCapabilities struct{ Core }
+
+func (h *MockHostCapabilities) HostCapabilities() (caps []vagrant.SystemCapability, err error) {
+	caps = []vagrant.SystemCapability{
+		vagrant.SystemCapability{Name: "test_cap", Platform: "testOS"}}
+	return
+}
+
+func (h *MockHostCapabilities) HostCapability(ctx context.Context, cap *vagrant.SystemCapability, args interface{}, e *vagrant.Environment) (result interface{}, err error) {
+	if args != nil {
+		arguments := args.([]interface{})
+		if arguments[0] == "pause" {
+			time.Sleep(1 * time.Second)
+		}
+		if len(arguments) > 0 {
+			result = []string{
+				cap.Name,
+				arguments[0].(string)}
+			return
+		}
+	}
+	result = []string{cap.Name}
+	return
+}
+
+type MockProviderCapabilities struct{ Core }
+
+func (p *MockProviderCapabilities) ProviderCapabilities() (caps []vagrant.ProviderCapability, err error) {
+	caps = []vagrant.ProviderCapability{
+		vagrant.ProviderCapability{Name: "test_cap", Provider: "testProvider"}}
+	return
+}
+
+func (p *MockProviderCapabilities) ProviderCapability(ctx context.Context, cap *vagrant.ProviderCapability, args interface{}, m *vagrant.Machine) (result interface{}, err error) {
+	if args != nil {
+		arguments := args.([]interface{})
+		if arguments[0] == "pause" {
+			time.Sleep(1 * time.Second)
+		}
+		if len(arguments) > 0 {
+			result = []string{
+				cap.Name,
+				arguments[0].(string)}
+			return
+		}
+	}
+	result = []string{cap.Name}
+	return
+}
+
+type MockConfig struct {
+	Core
+}
+
+func (c *MockConfig) ConfigAttributes() (attrs []string, err error) {
+	attrs = []string{"fubar", "foobar"}
+	return
+}
+
+func (c *MockConfig) ConfigLoad(ctx context.Context, data map[string]interface{}) (loaddata map[string]interface{}, err error) {
+	if data["pause"] == true {
+		time.Sleep(1 * time.Second)
+	}
+	loaddata = map[string]interface{}{
+		"test_key": "test_val"}
+	if data["test_key"] != nil {
+		loaddata["sent_key"] = data["test_key"]
+	}
+	return
+}
+
+func (c *MockConfig) ConfigValidate(ctx context.Context, data map[string]interface{}, m *vagrant.Machine) (errors []string, err error) {
+	errors = []string{"test error"}
+	if data["pause"] == true {
+		time.Sleep(1 * time.Second)
+	}
+	return
+}
+
+func (c *MockConfig) ConfigFinalize(ctx context.Context, data map[string]interface{}) (finaldata map[string]interface{}, err error) {
+	finaldata = make(map[string]interface{})
+	for key, tval := range data {
+		val, ok := tval.(string)
+		if !ok {
+			continue
+		}
+		finaldata[key] = val + "-updated"
+	}
+	if data["pause"] == true {
+		time.Sleep(1 * time.Second)
+	}
+	return
+}
+
+type MockProvider struct {
+	Core
+	vagrant.NoConfig
+	vagrant.NoGuestCapabilities
+	vagrant.NoHostCapabilities
+	vagrant.NoProviderCapabilities
+}
+
+func (c *MockProvider) Action(ctx context.Context, actionName string, m *vagrant.Machine) (actions []string, err error) {
+	switch actionName {
+	case "valid":
+		actions = []string{"self::DoTask"}
+	case "pause":
+		time.Sleep(1 * time.Second)
+	default:
+		err = errors.New("Unknown action requested")
+	}
+	return
+}
+
+func (c *MockProvider) IsInstalled(ctx context.Context, m *vagrant.Machine) (bool, error) {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	return true, nil
+}
+
+func (c *MockProvider) IsUsable(ctx context.Context, m *vagrant.Machine) (bool, error) {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	return true, nil
+}
+
+func (c *MockProvider) MachineIdChanged(ctx context.Context, m *vagrant.Machine) error {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	return nil
+}
+
+func (c *MockProvider) Name() string {
+	return "mock_provider"
+}
+
+func (c *MockProvider) RunAction(ctx context.Context, actionName string, args interface{}, m *vagrant.Machine) (r interface{}, err error) {
+	switch actionName {
+	case "send_output":
+		m.UI.Say("test_output_p")
+	case "pause":
+		time.Sleep(1 * time.Second)
+	case "valid":
+	default:
+		return nil, errors.New("invalid action name")
+	}
+	var arguments []interface{}
+	if args != nil {
+		arguments = args.([]interface{})
+	} else {
+		arguments = []interface{}{"unset"}
+	}
+	r = []string{
+		actionName,
+		arguments[0].(string)}
+	return
+}
+
+func (c *MockProvider) SshInfo(ctx context.Context, m *vagrant.Machine) (*vagrant.SshInfo, error) {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	return &vagrant.SshInfo{
+		Host: "localhost",
+		Port: 2222}, nil
+}
+
+func (c *MockProvider) State(ctx context.Context, m *vagrant.Machine) (*vagrant.MachineState, error) {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	return &vagrant.MachineState{
+		Id:        "default",
+		ShortDesc: "running"}, nil
+}
+
+func (c *MockProvider) Info() *vagrant.ProviderInfo {
+	return &vagrant.ProviderInfo{
+		Description: "Custom",
+		Priority:    10}
+}
+
+type MockSyncedFolder struct {
+	Core
+	vagrant.NoGuestCapabilities
+	vagrant.NoHostCapabilities
+}
+
+func (s *MockSyncedFolder) Cleanup(ctx context.Context, m *vagrant.Machine, opts vagrant.FolderOptions) error {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	if opts != nil {
+		err, _ := opts["error"].(bool)
+		ui, _ := opts["ui"].(bool)
+		if err {
+			return errors.New("cleanup error")
+		}
+		if ui {
+			m.UI.Say("test_output_sf")
+			return nil
+		}
+	}
+	return nil
+}
+
+func (s *MockSyncedFolder) Disable(ctx context.Context, m *vagrant.Machine, f vagrant.FolderList, opts vagrant.FolderOptions) error {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	if opts != nil && opts["error"].(bool) {
+		return errors.New("disable error")
+	}
+	return nil
+}
+
+func (s *MockSyncedFolder) Enable(ctx context.Context, m *vagrant.Machine, f vagrant.FolderList, opts vagrant.FolderOptions) error {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	if opts != nil && opts["error"].(bool) {
+		return errors.New("enable error")
+	}
+	return nil
+}
+
+func (s *MockSyncedFolder) Info() *vagrant.SyncedFolderInfo {
+	return &vagrant.SyncedFolderInfo{
+		Description: "mock_folder",
+		Priority:    100}
+}
+
+func (s *MockSyncedFolder) IsUsable(ctx context.Context, m *vagrant.Machine) (bool, error) {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	return true, nil
+}
+
+func (s *MockSyncedFolder) Name() string {
+	return "mock_folder"
+}
+
+func (s *MockSyncedFolder) Prepare(ctx context.Context, m *vagrant.Machine, f vagrant.FolderList, opts vagrant.FolderOptions) error {
+	if m.Name == "pause" {
+		time.Sleep(1 * time.Second)
+	}
+
+	if opts != nil && opts["error"].(bool) {
+		return errors.New("prepare error")
+	}
+	return nil
+}

ext/go-plugin/vagrant/plugin/proto/genproto

@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+
+echo -n "Parsing proto files and generating go output... "
+
+for i in *
+do
+    if [ -d "${i}" ]; then
+        protoc --proto_path=`go env GOPATH`/src --proto_path=. --go_out=plugins=grpc:. "${i}"/*.proto;
+        if [ $? -ne 0 ]; then
+            echo "failed!"
+            exit 1
+        fi
+    fi
+done
+
+protoc --proto_path=`go env GOPATH`/src --proto_path=. --go_out=plugins=grpc:. *.proto;
+
+if [ $? -ne 0 ]; then
+    echo "failed!"
+    exit 1
+fi
+
+echo "done!"

ext/go-plugin/vagrant/plugin/proto/vagrant.proto

@@ -0,0 +1,196 @@
+syntax = "proto3";
+package vagrant.proto;
+
+message Empty{}
+
+message Machine {
+  string machine = 1;
+}
+
+message Valid {
+  bool result = 1;
+}
+
+message Identifier {
+  string name = 1;
+}
+
+message PluginInfo {
+  string description = 1;
+  int64 priority = 2;
+}
+
+message Content {
+  string target = 1;
+  string value = 2;
+}
+
+message WriteResponse {
+  int32 length = 1;
+}
+
+service IO {
+  rpc Read(Identifier) returns (Content);
+  rpc Write(Content) returns (WriteResponse);
+}
+
+message SystemCapability {
+  string name = 1;
+  string platform = 2;
+}
+
+message ProviderCapability {
+  string name = 1;
+  string provider = 2;
+}
+
+message SystemCapabilityList {
+  repeated SystemCapability capabilities = 1;
+}
+
+message ProviderCapabilityList {
+  repeated ProviderCapability capabilities = 1;
+}
+
+message GenericResponse {
+  string result = 1;
+}
+
+message GuestCapabilityRequest {
+  SystemCapability capability = 1;
+  string machine = 2;
+  string arguments = 3;
+}
+
+message HostCapabilityRequest {
+  SystemCapability capability = 1;
+  string environment = 2;
+  string arguments = 3;
+}
+
+message ProviderCapabilityRequest {
+  ProviderCapability capability = 1;
+  string machine = 2;
+  string arguments = 3;
+}
+
+service GuestCapabilities {
+  rpc GuestCapabilities(Empty) returns (SystemCapabilityList);
+  rpc GuestCapability(GuestCapabilityRequest) returns (GenericResponse);
+  // IO helpers for streaming (copied from Stream service)
+  rpc Read(Identifier) returns (Content);
+  rpc Write(Content) returns (WriteResponse);
+}
+
+service HostCapabilities {
+  rpc HostCapabilities(Empty) returns (SystemCapabilityList);
+  rpc HostCapability(HostCapabilityRequest) returns (GenericResponse);
+  // IO helpers for streaming (copied from Stream service)
+  rpc Read(Identifier) returns (Content);
+  rpc Write(Content) returns (WriteResponse);
+}
+
+service ProviderCapabilities {
+  rpc ProviderCapabilities (Empty) returns (ProviderCapabilityList);
+  rpc ProviderCapability (ProviderCapabilityRequest) returns (GenericResponse);
+  // IO helpers for streaming (copied from Stream service)
+  rpc Read(Identifier) returns (Content);
+  rpc Write(Content) returns (WriteResponse);
+}
+
+message Configuration {
+  string data = 1;
+  string machine = 2;
+}
+
+message ListResponse {
+  repeated string items = 1;
+}
+
+service Config {
+  rpc ConfigAttributes(Empty) returns (ListResponse);
+  rpc ConfigLoad(Configuration) returns (Configuration);
+  rpc ConfigValidate(Configuration) returns (ListResponse);
+  rpc ConfigFinalize(Configuration) returns (Configuration);
+  // IO helpers for streaming (copied from Stream service)
+  rpc Read(Identifier) returns (Content);
+  rpc Write(Content) returns (WriteResponse);
+}
+
+message SyncedFolders {
+  string machine = 1;
+  string folders = 2;
+  string options = 3;
+}
+
+service SyncedFolder {
+  rpc Cleanup(SyncedFolders) returns (Empty);
+  rpc Disable(SyncedFolders) returns (Empty);
+  rpc Enable(SyncedFolders) returns (Empty);
+  rpc Info(Empty) returns (PluginInfo);
+  rpc IsUsable(Machine) returns (Valid);
+  rpc Name(Empty) returns (Identifier);
+  rpc Prepare(SyncedFolders) returns (Empty);
+  // IO helpers for streaming (copied from Stream service)
+  rpc Read(Identifier) returns (Content);
+  rpc Write(Content) returns (WriteResponse);
+  // Guest capabilities helpers (copied from GuestCapabilities service)
+  rpc GuestCapabilities(Empty) returns (SystemCapabilityList);
+  rpc GuestCapability(GuestCapabilityRequest) returns (GenericResponse);
+  // Host capabilities helpers (copied from GuestCapabilities service)
+  rpc HostCapabilities(Empty) returns (SystemCapabilityList);
+  rpc HostCapability(HostCapabilityRequest) returns (GenericResponse);
+}
+
+message GenericAction {
+  string name = 1;
+  string machine = 2;
+}
+
+message ExecuteAction {
+  string name = 1;
+  string data = 2;
+  string machine = 3;
+}
+
+message MachineSshInfo {
+  string host = 1;
+  int64 port = 2;
+  string private_key_path = 3;
+  string username = 4;
+}
+
+message MachineState {
+  string id = 1;
+  string short_description = 2;
+  string long_description = 3;
+}
+
+service Provider {
+  rpc Action(GenericAction) returns (ListResponse);
+  rpc Info(Empty) returns (PluginInfo);
+  rpc IsInstalled(Machine) returns (Valid);
+  rpc IsUsable(Machine) returns (Valid);
+  rpc MachineIdChanged(Machine) returns (Machine);
+  rpc Name(Empty) returns (Identifier);
+  rpc RunAction(ExecuteAction) returns (GenericResponse);
+  rpc SshInfo(Machine) returns (MachineSshInfo);
+  rpc State(Machine) returns (MachineState);
+  // IO helpers for streaming (copied from Stream service)
+  rpc Read(Identifier) returns (Content);
+  rpc Write(Content) returns (WriteResponse);
+  // Config helpers (copied from Config service)
+  rpc ConfigAttributes(Empty) returns (ListResponse);
+  rpc ConfigLoad(Configuration) returns (Configuration);
+  rpc ConfigValidate(Configuration) returns (ListResponse);
+  rpc ConfigFinalize(Configuration) returns (Configuration);
+  // Guest capabilities helpers (copied from GuestCapabilities service)
+  rpc GuestCapabilities(Empty) returns (SystemCapabilityList);
+  rpc GuestCapability(GuestCapabilityRequest) returns (GenericResponse);
+  // Host capabilities helpers (copied from HostCapabilities service)
+  rpc HostCapabilities(Empty) returns (SystemCapabilityList);
+  rpc HostCapability(HostCapabilityRequest) returns (GenericResponse);
+  // Provider capabilities helpers (copied from ProviderCapabilities service)
+  rpc ProviderCapabilities (Empty) returns (ProviderCapabilityList);
+  rpc ProviderCapability (ProviderCapabilityRequest) returns (GenericResponse);
+}

ext/go-plugin/vagrant/plugin/provider.go

@@ -0,0 +1,346 @@
+package plugin
+
+import (
+	"context"
+	"encoding/json"
+
+	"google.golang.org/grpc"
+
+	go_plugin "github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/plugin/proto"
+
+	"github.com/LK4D4/joincontext"
+)
+
+type Provider interface {
+	vagrant.Provider
+	Meta
+}
+
+type ProviderPlugin struct {
+	go_plugin.NetRPCUnsupportedPlugin
+	Impl Provider
+}
+
+type GRPCProviderClient struct {
+	GRPCCoreClient
+	GRPCConfigClient
+	GRPCGuestCapabilitiesClient
+	GRPCHostCapabilitiesClient
+	GRPCProviderCapabilitiesClient
+	GRPCIOClient
+	client  vagrant_proto.ProviderClient
+	doneCtx context.Context
+}
+
+func (c *GRPCProviderClient) Action(ctx context.Context, actionName string, m *vagrant.Machine) (r []string, err error) {
+	machData, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.Action(jctx, &vagrant_proto.GenericAction{
+		Name:    actionName,
+		Machine: machData})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	r = resp.Items
+	return
+}
+
+func (c *GRPCProviderClient) Info() *vagrant.ProviderInfo {
+	ctx := context.Background()
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.Info(jctx, &vagrant_proto.Empty{})
+	if err != nil {
+		return &vagrant.ProviderInfo{}
+	}
+	return &vagrant.ProviderInfo{
+		Description: resp.Description,
+		Priority:    resp.Priority}
+}
+
+func (c *GRPCProviderClient) IsInstalled(ctx context.Context, m *vagrant.Machine) (r bool, err error) {
+	machData, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.IsInstalled(jctx, &vagrant_proto.Machine{
+		Machine: machData})
+	if err != nil {
+		return false, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	r = resp.Result
+	return
+}
+
+func (c *GRPCProviderClient) IsUsable(ctx context.Context, m *vagrant.Machine) (r bool, err error) {
+	machData, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.IsUsable(jctx, &vagrant_proto.Machine{
+		Machine: machData})
+	if err != nil {
+		return false, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	r = resp.Result
+	return
+}
+
+func (c *GRPCProviderClient) MachineIdChanged(ctx context.Context, m *vagrant.Machine) (err error) {
+	machData, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	_, err = c.client.MachineIdChanged(jctx, &vagrant_proto.Machine{
+		Machine: machData})
+	if err != nil {
+		return handleGrpcError(err, c.doneCtx, ctx)
+	}
+	return
+}
+
+func (c *GRPCProviderClient) RunAction(ctx context.Context, actName string, args interface{}, m *vagrant.Machine) (r interface{}, err error) {
+	machData, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	runData, err := json.Marshal(args)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.RunAction(jctx, &vagrant_proto.ExecuteAction{
+		Name:    actName,
+		Data:    string(runData),
+		Machine: machData})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	err = json.Unmarshal([]byte(resp.Result), &r)
+	if err != nil {
+		return
+	}
+	return
+}
+
+func (c *GRPCProviderClient) SshInfo(ctx context.Context, m *vagrant.Machine) (r *vagrant.SshInfo, err error) {
+	machData, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.SshInfo(jctx, &vagrant_proto.Machine{
+		Machine: machData})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	r = &vagrant.SshInfo{
+		Host:           resp.Host,
+		Port:           resp.Port,
+		PrivateKeyPath: resp.PrivateKeyPath,
+		Username:       resp.Username}
+	return
+}
+
+func (c *GRPCProviderClient) State(ctx context.Context, m *vagrant.Machine) (r *vagrant.MachineState, err error) {
+	machData, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.State(jctx, &vagrant_proto.Machine{
+		Machine: machData})
+	if err != nil {
+		return nil, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	r = &vagrant.MachineState{
+		Id:        resp.Id,
+		ShortDesc: resp.ShortDescription,
+		LongDesc:  resp.LongDescription}
+	return
+}
+
+func (c *GRPCProviderClient) Name() string {
+	ctx := context.Background()
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.Name(jctx, &vagrant_proto.Empty{})
+	if err != nil {
+		return ""
+	}
+	return resp.Name
+}
+
+func (p *ProviderPlugin) GRPCClient(ctx context.Context, broker *go_plugin.GRPCBroker, c *grpc.ClientConn) (interface{}, error) {
+	client := vagrant_proto.NewProviderClient(c)
+	return &GRPCProviderClient{
+		GRPCConfigClient: GRPCConfigClient{
+			client:  client,
+			doneCtx: ctx},
+		GRPCGuestCapabilitiesClient: GRPCGuestCapabilitiesClient{
+			client:  client,
+			doneCtx: ctx},
+		GRPCHostCapabilitiesClient: GRPCHostCapabilitiesClient{
+			client:  client,
+			doneCtx: ctx},
+		GRPCProviderCapabilitiesClient: GRPCProviderCapabilitiesClient{
+			client:  client,
+			doneCtx: ctx},
+		GRPCIOClient: GRPCIOClient{
+			client:  client,
+			doneCtx: ctx},
+		client:  client,
+		doneCtx: ctx,
+	}, nil
+}
+
+func (p *ProviderPlugin) GRPCServer(broker *go_plugin.GRPCBroker, s *grpc.Server) error {
+	p.Impl.Init()
+	vagrant_proto.RegisterProviderServer(s, &GRPCProviderServer{
+		Impl: p.Impl,
+		GRPCConfigServer: GRPCConfigServer{
+			Impl: p.Impl},
+		GRPCGuestCapabilitiesServer: GRPCGuestCapabilitiesServer{
+			Impl: p.Impl},
+		GRPCHostCapabilitiesServer: GRPCHostCapabilitiesServer{
+			Impl: p.Impl},
+		GRPCProviderCapabilitiesServer: GRPCProviderCapabilitiesServer{
+			Impl: p.Impl},
+		GRPCIOServer: GRPCIOServer{
+			Impl: p.Impl}})
+	return nil
+}
+
+type GRPCProviderServer struct {
+	GRPCIOServer
+	GRPCConfigServer
+	GRPCGuestCapabilitiesServer
+	GRPCHostCapabilitiesServer
+	GRPCProviderCapabilitiesServer
+	Impl Provider
+}
+
+func (s *GRPCProviderServer) Action(ctx context.Context, req *vagrant_proto.GenericAction) (resp *vagrant_proto.ListResponse, err error) {
+	resp = &vagrant_proto.ListResponse{}
+	m, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	r, err := s.Impl.Action(ctx, req.Name, m)
+	if err != nil {
+		return
+	}
+	resp.Items = r
+	return
+}
+
+func (s *GRPCProviderServer) RunAction(ctx context.Context, req *vagrant_proto.ExecuteAction) (resp *vagrant_proto.GenericResponse, err error) {
+	resp = &vagrant_proto.GenericResponse{}
+	var args interface{}
+	m, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	if err = json.Unmarshal([]byte(req.Data), &args); err != nil {
+		return
+	}
+	r, err := s.Impl.RunAction(ctx, req.Name, args, m)
+	if err != nil {
+		return
+	}
+	result, err := json.Marshal(r)
+	if err != nil {
+		return
+	}
+	resp.Result = string(result)
+	return
+}
+
+func (s *GRPCProviderServer) Info(ctx context.Context, req *vagrant_proto.Empty) (resp *vagrant_proto.PluginInfo, err error) {
+	resp = &vagrant_proto.PluginInfo{}
+	r := s.Impl.Info()
+	resp.Description = r.Description
+	resp.Priority = r.Priority
+	return
+}
+
+func (s *GRPCProviderServer) IsInstalled(ctx context.Context, req *vagrant_proto.Machine) (resp *vagrant_proto.Valid, err error) {
+	resp = &vagrant_proto.Valid{}
+	m, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	resp.Result, err = s.Impl.IsInstalled(ctx, m)
+	return
+}
+
+func (s *GRPCProviderServer) IsUsable(ctx context.Context, req *vagrant_proto.Machine) (resp *vagrant_proto.Valid, err error) {
+	resp = &vagrant_proto.Valid{}
+	m, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	resp.Result, err = s.Impl.IsUsable(ctx, m)
+	return
+}
+
+func (s *GRPCProviderServer) SshInfo(ctx context.Context, req *vagrant_proto.Machine) (resp *vagrant_proto.MachineSshInfo, err error) {
+	resp = &vagrant_proto.MachineSshInfo{}
+	m, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	r, err := s.Impl.SshInfo(ctx, m)
+	if err != nil {
+		return
+	}
+	resp.Host = r.Host
+	resp.Port = r.Port
+	resp.Username = r.Username
+	resp.PrivateKeyPath = r.PrivateKeyPath
+	return
+}
+
+func (s *GRPCProviderServer) State(ctx context.Context, req *vagrant_proto.Machine) (resp *vagrant_proto.MachineState, err error) {
+	resp = &vagrant_proto.MachineState{}
+	m, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	r, err := s.Impl.State(ctx, m)
+	if err != nil {
+		return
+	}
+	resp.Id = r.Id
+	resp.ShortDescription = r.ShortDesc
+	resp.LongDescription = r.LongDesc
+	return
+}
+
+func (s *GRPCProviderServer) MachineIdChanged(ctx context.Context, req *vagrant_proto.Machine) (resp *vagrant_proto.Machine, err error) {
+	resp = &vagrant_proto.Machine{}
+	m, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	if err = s.Impl.MachineIdChanged(ctx, m); err != nil {
+		return
+	}
+	mdata, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	resp = &vagrant_proto.Machine{Machine: mdata}
+	return
+}
+
+func (s *GRPCProviderServer) Name(ctx context.Context, req *vagrant_proto.Empty) (*vagrant_proto.Identifier, error) {
+	return &vagrant_proto.Identifier{Name: s.Impl.Name()}, nil
+}

ext/go-plugin/vagrant/plugin/provider_test.go

@@ -0,0 +1,667 @@
+package plugin
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+)
+
+func TestProvider_Action(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	resp, err := impl.Action(context.Background(), "valid", &vagrant.Machine{})
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if resp[0] != "self::DoTask" {
+		t.Errorf("%s != self::DoTask", resp[0])
+	}
+}
+
+func TestProvider_Action_invalid(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	_, err = impl.Action(context.Background(), "invalid", &vagrant.Machine{})
+	if err == nil {
+		t.Errorf("illegal action")
+	}
+}
+
+func TestProvider_Action_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.Action(ctx, "pause", &vagrant.Machine{})
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestProvider_Action_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.Action(ctx, "pause", &vagrant.Machine{})
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestProvider_IsInstalled(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	installed, err := impl.IsInstalled(context.Background(), &vagrant.Machine{})
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if !installed {
+		t.Errorf("bad result")
+	}
+}
+
+func TestProvider_IsInstalled_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.IsInstalled(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestProvider_IsInstalled_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.IsInstalled(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+func TestProvider_IsUsable(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+	usable, err := impl.IsUsable(context.Background(), &vagrant.Machine{})
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if !usable {
+		t.Errorf("bad result")
+	}
+}
+
+func TestProvider_IsUsable_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.IsUsable(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestProvider_IsUsable_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.IsUsable(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+func TestProvider_MachineIdChanged(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	err = impl.MachineIdChanged(context.Background(), &vagrant.Machine{})
+	if err != nil {
+		t.Errorf("err: %s", err)
+	}
+}
+
+func TestProvider_MachineIdChanged_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	err = impl.MachineIdChanged(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestProvider_MachineIdChanged_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	err = impl.MachineIdChanged(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestProvider_Name(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	resp := impl.Name()
+	if resp != "mock_provider" {
+		t.Errorf("%s != mock_provider", resp)
+	}
+}
+
+func TestProvider_RunAction(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	args := []string{"test_arg", "other_arg"}
+	m := &vagrant.Machine{}
+
+	resp, err := impl.RunAction(context.Background(), "valid", args, m)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+
+	result := resp.([]interface{})
+	if result[0] != "valid" {
+		t.Errorf("%s != valid", result[0])
+	}
+	if result[1] != "test_arg" {
+		t.Errorf("%s != test_arg", result[1])
+	}
+}
+
+func TestProvider_RunAction_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	args := []string{"test_arg", "other_arg"}
+	m := &vagrant.Machine{}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.RunAction(ctx, "pause", args, m)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestProvider_RunAction_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	args := []string{"test_arg", "other_arg"}
+	m := &vagrant.Machine{}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.RunAction(ctx, "pause", args, m)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestProvider_RunAction_invalid(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	args := []string{"test_arg", "other_arg"}
+	m := &vagrant.Machine{}
+
+	_, err = impl.RunAction(context.Background(), "invalid", args, m)
+	if err == nil {
+		t.Fatalf("illegal action run")
+	}
+}
+
+func TestProvider_SshInfo(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	resp, err := impl.SshInfo(context.Background(), &vagrant.Machine{})
+	if err != nil {
+		t.Fatalf("invalid resp: %s", err)
+	}
+
+	if resp.Host != "localhost" {
+		t.Errorf("%s != localhost", resp.Host)
+	}
+	if resp.Port != 2222 {
+		t.Errorf("%d != 2222", resp.Port)
+	}
+}
+
+func TestProvider_SshInfo_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.SshInfo(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.Canceled {
+		t.Fatalf("invalid resp: %s", err)
+	}
+}
+
+func TestProvider_SshInfo_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.SshInfo(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.DeadlineExceeded {
+		t.Fatalf("invalid resp: %s", err)
+	}
+}
+
+func TestProvider_State(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	resp, err := impl.State(context.Background(), &vagrant.Machine{})
+	if err != nil {
+		t.Fatalf("invalid resp: %s", err)
+	}
+
+	if resp.Id != "default" {
+		t.Errorf("%s != default", resp.Id)
+	}
+	if resp.ShortDesc != "running" {
+		t.Errorf("%s != running", resp.ShortDesc)
+	}
+}
+
+func TestProvider_State_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.State(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.Canceled {
+		t.Fatalf("invalid resp: %s", err)
+	}
+}
+
+func TestProvider_State_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.State(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.DeadlineExceeded {
+		t.Fatalf("invalid resp: %s", err)
+	}
+}
+
+func TestProvider_Info(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	resp := impl.Info()
+
+	if resp.Description != "Custom" {
+		t.Errorf("%s != Custom", resp.Description)
+	}
+	if resp.Priority != 10 {
+		t.Errorf("%d != 10", resp.Priority)
+	}
+}
+
+func TestProvider_MachineUI_output(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"provider": &ProviderPlugin{Impl: &MockProvider{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("provider")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(Provider)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx := context.Background()
+	go func() {
+		_, err = impl.RunAction(ctx, "send_output", nil, &vagrant.Machine{})
+		if err != nil {
+			t.Fatalf("bad resp: %s", err)
+		}
+	}()
+
+	resp, err := impl.Read("stdout")
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+
+	if !strings.Contains(resp, "test_output_p") {
+		t.Errorf("%s !~ test_output_p", resp)
+	}
+}

ext/go-plugin/vagrant/plugin/synced_folder.go

@@ -0,0 +1,283 @@
+package plugin
+
+import (
+	"context"
+	"encoding/json"
+
+	"google.golang.org/grpc"
+
+	go_plugin "github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant/plugin/proto"
+
+	"github.com/LK4D4/joincontext"
+)
+
+type SyncedFolder interface {
+	vagrant.SyncedFolder
+	Meta
+}
+
+type SyncedFolderPlugin struct {
+	go_plugin.NetRPCUnsupportedPlugin
+	Impl SyncedFolder
+}
+
+type GRPCSyncedFolderClient struct {
+	GRPCCoreClient
+	GRPCGuestCapabilitiesClient
+	GRPCHostCapabilitiesClient
+	GRPCIOClient
+	client  vagrant_proto.SyncedFolderClient
+	doneCtx context.Context
+}
+
+func (c *GRPCSyncedFolderClient) Cleanup(ctx context.Context, m *vagrant.Machine, o vagrant.FolderOptions) (err error) {
+	machine, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	opts, err := json.Marshal(o)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	_, err = c.client.Cleanup(jctx, &vagrant_proto.SyncedFolders{
+		Machine: machine,
+		Options: string(opts)})
+	return handleGrpcError(err, c.doneCtx, ctx)
+}
+
+func (c *GRPCSyncedFolderClient) Disable(ctx context.Context, m *vagrant.Machine, f vagrant.FolderList, o vagrant.FolderOptions) (err error) {
+	machine, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	folders, err := json.Marshal(f)
+	if err != nil {
+		return
+	}
+	opts, err := json.Marshal(o)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	_, err = c.client.Disable(jctx, &vagrant_proto.SyncedFolders{
+		Machine: machine,
+		Folders: string(folders),
+		Options: string(opts)})
+	return handleGrpcError(err, c.doneCtx, ctx)
+}
+
+func (c *GRPCSyncedFolderClient) Enable(ctx context.Context, m *vagrant.Machine, f vagrant.FolderList, o vagrant.FolderOptions) (err error) {
+	machine, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	folders, err := json.Marshal(f)
+	if err != nil {
+		return
+	}
+	opts, err := json.Marshal(o)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	_, err = c.client.Enable(jctx, &vagrant_proto.SyncedFolders{
+		Machine: machine,
+		Folders: string(folders),
+		Options: string(opts)})
+	return handleGrpcError(err, c.doneCtx, ctx)
+}
+
+func (c *GRPCSyncedFolderClient) Info() *vagrant.SyncedFolderInfo {
+	resp, err := c.client.Info(context.Background(), &vagrant_proto.Empty{})
+	if err != nil {
+		return &vagrant.SyncedFolderInfo{}
+	}
+	return &vagrant.SyncedFolderInfo{
+		Description: resp.Description,
+		Priority:    resp.Priority}
+}
+
+func (c *GRPCSyncedFolderClient) IsUsable(ctx context.Context, m *vagrant.Machine) (u bool, err error) {
+	machine, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	resp, err := c.client.IsUsable(jctx, &vagrant_proto.Machine{
+		Machine: machine})
+	if err != nil {
+		return false, handleGrpcError(err, c.doneCtx, ctx)
+	}
+	u = resp.Result
+	return
+}
+
+func (c *GRPCSyncedFolderClient) Name() string {
+	resp, err := c.client.Name(context.Background(), &vagrant_proto.Empty{})
+	if err != nil {
+		return ""
+	}
+	return resp.Name
+}
+
+func (c *GRPCSyncedFolderClient) Prepare(ctx context.Context, m *vagrant.Machine, f vagrant.FolderList, o vagrant.FolderOptions) (err error) {
+	machine, err := vagrant.DumpMachine(m)
+	if err != nil {
+		return
+	}
+	folders, err := json.Marshal(f)
+	if err != nil {
+		return
+	}
+	opts, err := json.Marshal(o)
+	if err != nil {
+		return
+	}
+	jctx, _ := joincontext.Join(ctx, c.doneCtx)
+	_, err = c.client.Prepare(jctx, &vagrant_proto.SyncedFolders{
+		Machine: machine,
+		Folders: string(folders),
+		Options: string(opts)})
+	return handleGrpcError(err, c.doneCtx, ctx)
+}
+
+type GRPCSyncedFolderServer struct {
+	GRPCGuestCapabilitiesServer
+	GRPCHostCapabilitiesServer
+	GRPCIOServer
+	Impl SyncedFolder
+}
+
+func (s *GRPCSyncedFolderServer) Cleanup(ctx context.Context, req *vagrant_proto.SyncedFolders) (resp *vagrant_proto.Empty, err error) {
+	resp = &vagrant_proto.Empty{}
+	machine, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	var options vagrant.FolderOptions
+	err = json.Unmarshal([]byte(req.Options), &options)
+	if err != nil {
+		return
+	}
+	err = s.Impl.Cleanup(ctx, machine, options)
+	return
+}
+
+func (s *GRPCSyncedFolderServer) Disable(ctx context.Context, req *vagrant_proto.SyncedFolders) (resp *vagrant_proto.Empty, err error) {
+	resp = &vagrant_proto.Empty{}
+	machine, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	var folders vagrant.FolderList
+	err = json.Unmarshal([]byte(req.Folders), &folders)
+	if err != nil {
+		return
+	}
+	var options vagrant.FolderOptions
+	err = json.Unmarshal([]byte(req.Options), &options)
+	if err != nil {
+		return
+	}
+	err = s.Impl.Disable(ctx, machine, folders, options)
+	return
+}
+
+func (s *GRPCSyncedFolderServer) Enable(ctx context.Context, req *vagrant_proto.SyncedFolders) (resp *vagrant_proto.Empty, err error) {
+	resp = &vagrant_proto.Empty{}
+	machine, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	var folders vagrant.FolderList
+	err = json.Unmarshal([]byte(req.Folders), &folders)
+	if err != nil {
+		return
+	}
+	var options vagrant.FolderOptions
+	err = json.Unmarshal([]byte(req.Options), &options)
+	if err != nil {
+		return
+	}
+	err = s.Impl.Enable(ctx, machine, folders, options)
+	return
+}
+
+func (s *GRPCSyncedFolderServer) Info(ctx context.Context, req *vagrant_proto.Empty) (resp *vagrant_proto.PluginInfo, err error) {
+	resp = &vagrant_proto.PluginInfo{}
+	r := s.Impl.Info()
+	resp.Description = r.Description
+	resp.Priority = r.Priority
+	return
+}
+
+func (s *GRPCSyncedFolderServer) IsUsable(ctx context.Context, req *vagrant_proto.Machine) (resp *vagrant_proto.Valid, err error) {
+	resp = &vagrant_proto.Valid{}
+	machine, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	r, err := s.Impl.IsUsable(ctx, machine)
+	if err != nil {
+		return
+	}
+	resp.Result = r
+	return
+}
+
+func (s *GRPCSyncedFolderServer) Name(_ context.Context, req *vagrant_proto.Empty) (*vagrant_proto.Identifier, error) {
+	return &vagrant_proto.Identifier{Name: s.Impl.Name()}, nil
+}
+
+func (s *GRPCSyncedFolderServer) Prepare(ctx context.Context, req *vagrant_proto.SyncedFolders) (resp *vagrant_proto.Empty, err error) {
+	resp = &vagrant_proto.Empty{}
+	machine, err := vagrant.LoadMachine(req.Machine, s.Impl)
+	if err != nil {
+		return
+	}
+	var folders vagrant.FolderList
+	err = json.Unmarshal([]byte(req.Folders), &folders)
+	if err != nil {
+		return
+	}
+	var options vagrant.FolderOptions
+	err = json.Unmarshal([]byte(req.Options), &options)
+	if err != nil {
+		return
+	}
+	err = s.Impl.Prepare(ctx, machine, folders, options)
+	return
+}
+
+func (f *SyncedFolderPlugin) GRPCServer(broker *go_plugin.GRPCBroker, s *grpc.Server) error {
+	f.Impl.Init()
+	vagrant_proto.RegisterSyncedFolderServer(s,
+		&GRPCSyncedFolderServer{
+			Impl: f.Impl,
+			GRPCIOServer: GRPCIOServer{
+				Impl: f.Impl},
+			GRPCGuestCapabilitiesServer: GRPCGuestCapabilitiesServer{
+				Impl: f.Impl},
+			GRPCHostCapabilitiesServer: GRPCHostCapabilitiesServer{
+				Impl: f.Impl}})
+	return nil
+}
+
+func (f *SyncedFolderPlugin) GRPCClient(ctx context.Context, broker *go_plugin.GRPCBroker, c *grpc.ClientConn) (interface{}, error) {
+	client := vagrant_proto.NewSyncedFolderClient(c)
+	return &GRPCSyncedFolderClient{
+		GRPCIOClient: GRPCIOClient{
+			client:  client,
+			doneCtx: ctx},
+		GRPCGuestCapabilitiesClient: GRPCGuestCapabilitiesClient{
+			client:  client,
+			doneCtx: ctx},
+		GRPCHostCapabilitiesClient: GRPCHostCapabilitiesClient{
+			client:  client,
+			doneCtx: ctx},
+		client:  client,
+		doneCtx: ctx}, nil
+}

ext/go-plugin/vagrant/plugin/synced_folder_test.go

@@ -0,0 +1,562 @@
+package plugin
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/hashicorp/go-plugin"
+	"github.com/hashicorp/vagrant/ext/go-plugin/vagrant"
+)
+
+func TestSyncedFolder_Cleanup(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	err = impl.Cleanup(context.Background(), &vagrant.Machine{}, nil)
+	if err != nil {
+		t.Fatalf("bad resp: %#v", err)
+	}
+}
+
+func TestSyncedFolder_Cleanup_error(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	args := map[string]interface{}{
+		"error": true}
+
+	err = impl.Cleanup(context.Background(), &vagrant.Machine{}, args)
+	if err == nil {
+		t.Fatalf("illegal cleanup")
+	}
+	if err.Error() != "cleanup error" {
+		t.Errorf("%s != cleanup error", err.Error())
+	}
+}
+
+func TestSyncedFolder_Cleanup_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	err = impl.Cleanup(ctx, &vagrant.Machine{Name: "pause"}, nil)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Cleanup_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	err = impl.Cleanup(ctx, &vagrant.Machine{Name: "pause"}, nil)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Disable(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	err = impl.Disable(context.Background(), &vagrant.Machine{}, nil, nil)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Disable_error(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	folders := map[string]interface{}{
+		"folder_name": "options"}
+	args := map[string]interface{}{
+		"error": true}
+
+	err = impl.Disable(context.Background(), &vagrant.Machine{}, folders, args)
+	if err == nil {
+		t.Fatalf("illegal disable")
+	}
+	if err.Error() != "disable error" {
+		t.Errorf("%s != disable error", err.Error())
+	}
+}
+
+func TestSyncedFolder_Disable_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	err = impl.Disable(ctx, &vagrant.Machine{Name: "pause"}, nil, nil)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Disable_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	err = impl.Disable(ctx, &vagrant.Machine{Name: "pause"}, nil, nil)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Enable(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	err = impl.Enable(context.Background(), &vagrant.Machine{}, nil, nil)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Enable_error(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	folders := map[string]interface{}{
+		"folder_name": "options"}
+	args := map[string]interface{}{
+		"error": true}
+
+	err = impl.Enable(context.Background(), &vagrant.Machine{}, folders, args)
+	if err == nil {
+		t.Fatalf("illegal enable")
+	}
+	if err.Error() != "enable error" {
+		t.Errorf("%s != enable error", err.Error())
+	}
+}
+
+func TestSyncedFolder_Enable_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	err = impl.Enable(ctx, &vagrant.Machine{Name: "pause"}, nil, nil)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Enable_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	err = impl.Enable(ctx, &vagrant.Machine{Name: "pause"}, nil, nil)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Prepare(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	err = impl.Prepare(context.Background(), &vagrant.Machine{}, nil, nil)
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Prepare_error(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	folders := map[string]interface{}{
+		"folder_name": "options"}
+	args := map[string]interface{}{
+		"error": true}
+
+	err = impl.Prepare(context.Background(), &vagrant.Machine{}, folders, args)
+	if err == nil {
+		t.Fatalf("illegal prepare")
+	}
+	if err.Error() != "prepare error" {
+		t.Errorf("%s != prepare error", err.Error())
+	}
+}
+
+func TestSyncedFolder_Prepare_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	err = impl.Prepare(ctx, &vagrant.Machine{Name: "pause"}, nil, nil)
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Prepare_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	err = impl.Prepare(ctx, &vagrant.Machine{Name: "pause"}, nil, nil)
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+func TestSyncedFolder_Info(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	resp := impl.Info()
+	if resp == nil {
+		t.Fatalf("bad resp")
+	}
+
+	if resp.Description != "mock_folder" {
+		t.Errorf("%s != mock_folder", resp.Description)
+	}
+	if resp.Priority != 100 {
+		t.Errorf("%d != 100", resp.Priority)
+	}
+}
+
+func TestSyncedFolder_IsUsable(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	resp, err := impl.IsUsable(context.Background(), &vagrant.Machine{})
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if !resp {
+		t.Errorf("bad result")
+	}
+}
+
+func TestSyncedFolder_IsUsable_context_cancel(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+	go func() {
+		time.Sleep(2 * time.Millisecond)
+		cancel()
+	}()
+	_, err = impl.IsUsable(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.Canceled {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_IsUsable_context_timeout(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Millisecond)
+	defer cancel()
+	_, err = impl.IsUsable(ctx, &vagrant.Machine{Name: "pause"})
+	if err != context.DeadlineExceeded {
+		t.Fatalf("bad resp: %s", err)
+	}
+}
+
+func TestSyncedFolder_Name(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	resp := impl.Name()
+	if resp != "mock_folder" {
+		t.Errorf("%s != mock_folder", resp)
+	}
+}
+
+func TestSyncedFolder_MachineUI_output(t *testing.T) {
+	client, server := plugin.TestPluginGRPCConn(t, map[string]plugin.Plugin{
+		"folder": &SyncedFolderPlugin{Impl: &MockSyncedFolder{}}})
+	defer server.Stop()
+	defer client.Close()
+
+	raw, err := client.Dispense("folder")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	impl, ok := raw.(SyncedFolder)
+	if !ok {
+		t.Fatalf("bad %#v", raw)
+	}
+
+	go func() {
+		err := impl.Cleanup(context.Background(), &vagrant.Machine{}, map[string]interface{}{"ui": true})
+		if err != nil {
+			t.Fatalf("bad resp: %s", err)
+		}
+	}()
+
+	resp, err := impl.Read("stdout")
+	if err != nil {
+		t.Fatalf("bad resp: %s", err)
+	}
+	if !strings.Contains(resp, "test_output") {
+		t.Errorf("%s !~ test_output", resp)
+	}
+}

ext/go-plugin/vagrant/provider.go

@@ -0,0 +1,27 @@
+package vagrant
+
+import (
+	"context"
+)
+
+type Provider interface {
+	Info() *ProviderInfo
+	Action(ctx context.Context, actionName string, machData *Machine) ([]string, error)
+	IsInstalled(ctx context.Context, machData *Machine) (bool, error)
+	IsUsable(ctx context.Context, machData *Machine) (bool, error)
+	MachineIdChanged(ctx context.Context, machData *Machine) error
+	Name() string
+	RunAction(ctx context.Context, actionName string, args interface{}, machData *Machine) (interface{}, error)
+	SshInfo(ctx context.Context, machData *Machine) (*SshInfo, error)
+	State(ctx context.Context, machData *Machine) (*MachineState, error)
+
+	Config
+	GuestCapabilities
+	HostCapabilities
+	ProviderCapabilities
+}
+
+type ProviderInfo struct {
+	Description string `json:"description"`
+	Priority    int64  `json:"priority"`
+}

ext/go-plugin/vagrant/ssh_info.go

@@ -0,0 +1,8 @@
+package vagrant
+
+type SshInfo struct {
+	Host           string `json:"host"`
+	Port           int64  `json:"port"`
+	Username       string `json:"username"`
+	PrivateKeyPath string `json:"private_key_path"`
+}

ext/go-plugin/vagrant/synced_folder.go

@@ -0,0 +1,26 @@
+package vagrant
+
+import (
+	"context"
+)
+
+type FolderList map[string]interface{}
+type FolderOptions map[string]interface{}
+
+type SyncedFolderInfo struct {
+	Description string `json:"description"`
+	Priority    int64  `json:"priority"`
+}
+
+type SyncedFolder interface {
+	Cleanup(ctx context.Context, m *Machine, opts FolderOptions) error
+	Disable(ctx context.Context, m *Machine, f FolderList, opts FolderOptions) error
+	Enable(ctx context.Context, m *Machine, f FolderList, opts FolderOptions) error
+	Info() *SyncedFolderInfo
+	IsUsable(ctx context.Context, m *Machine) (bool, error)
+	Name() string
+	Prepare(ctx context.Context, m *Machine, f FolderList, opts FolderOptions) error
+
+	GuestCapabilities
+	HostCapabilities
+}

ext/go-plugin/vagrant/ui.go

@@ -0,0 +1,472 @@
+package vagrant
+
+import (
+	"bufio"
+	"bytes"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"os/signal"
+	"runtime"
+	"strings"
+	"sync"
+	"syscall"
+	"time"
+	"unicode"
+)
+
+type UiColor uint
+
+const (
+	UiColorRed     UiColor = 31
+	UiColorGreen           = 32
+	UiColorYellow          = 33
+	UiColorBlue            = 34
+	UiColorMagenta         = 35
+	UiColorCyan            = 36
+)
+
+type UiChannel uint
+
+const (
+	UiOutput UiChannel = 1
+	UiError            = 2
+)
+
+var logger = DefaultLogger().Named("ui")
+
+type Options struct {
+	Channel UiChannel
+	NewLine bool
+}
+
+var defaultOptions = &Options{
+	Channel: UiOutput,
+	NewLine: true,
+}
+
+// The Ui interface handles all communication for Vagrant with the outside
+// world. This sort of control allows us to strictly control how output
+// is formatted and various levels of output.
+type Ui interface {
+	Ask(string) (string, error)
+	Detail(string)
+	Info(string)
+	Error(string)
+	Machine(string, ...string)
+	Message(string, *Options)
+	Output(string)
+	Say(string)
+	Success(string)
+	Warn(string)
+}
+
+// The BasicUI is a UI that reads and writes from a standard Go reader
+// and writer. It is safe to be called from multiple goroutines. Machine
+// readable output is simply logged for this UI.
+type BasicUi struct {
+	Reader      io.Reader
+	Writer      io.Writer
+	ErrorWriter io.Writer
+	l           sync.Mutex
+	interrupted bool
+	scanner     *bufio.Scanner
+}
+
+var _ Ui = new(BasicUi)
+
+func (rw *BasicUi) Ask(query string) (string, error) {
+	rw.l.Lock()
+	defer rw.l.Unlock()
+
+	if rw.interrupted {
+		return "", errors.New("interrupted")
+	}
+
+	if rw.scanner == nil {
+		rw.scanner = bufio.NewScanner(rw.Reader)
+	}
+	sigCh := make(chan os.Signal, 1)
+	signal.Notify(sigCh, os.Interrupt, syscall.SIGTERM)
+	defer signal.Stop(sigCh)
+
+	logger.Info("ask", query)
+	if query != "" {
+		if _, err := fmt.Fprint(rw.Writer, query+" "); err != nil {
+			return "", err
+		}
+	}
+
+	result := make(chan string, 1)
+	go func() {
+		var line string
+		if rw.scanner.Scan() {
+			line = rw.scanner.Text()
+		}
+		if err := rw.scanner.Err(); err != nil {
+			logger.Error("scan failure", "error", err)
+			return
+		}
+		result <- line
+	}()
+
+	select {
+	case line := <-result:
+		return line, nil
+	case <-sigCh:
+		// Print a newline so that any further output starts properly
+		// on a new line.
+		fmt.Fprintln(rw.Writer)
+
+		// Mark that we were interrupted so future Ask calls fail.
+		rw.interrupted = true
+
+		return "", errors.New("interrupted")
+	}
+}
+
+func (rw *BasicUi) Detail(message string)  { rw.Say(message) }
+func (rw *BasicUi) Info(message string)    { rw.Say(message) }
+func (rw *BasicUi) Output(message string)  { rw.Say(message) }
+func (rw *BasicUi) Success(message string) { rw.Say(message) }
+func (rw *BasicUi) Warn(message string)    { rw.Say(message) }
+
+func (rw *BasicUi) Say(message string) {
+	rw.Message(message, nil)
+}
+
+func (rw *BasicUi) Message(message string, opts *Options) {
+	rw.l.Lock()
+	defer rw.l.Unlock()
+
+	if opts == nil {
+		opts = &Options{Channel: UiOutput, NewLine: true}
+	}
+
+	logger.Debug("write message", "content", message, "options", opts)
+	target := rw.Writer
+	if opts.Channel == UiError {
+		if rw.ErrorWriter == nil {
+			logger.Error("error writer unset using writer")
+		} else {
+			target = rw.ErrorWriter
+		}
+	}
+	suffix := ""
+	if opts.NewLine {
+		suffix = "\n"
+	}
+
+	_, err := fmt.Fprint(target, message+suffix)
+	if err != nil {
+		logger.Error("write failure", "error", err)
+	}
+}
+
+func (rw *BasicUi) Error(message string) {
+	rw.Message(message, &Options{Channel: UiError, NewLine: true})
+}
+
+func (rw *BasicUi) Machine(t string, args ...string) {
+	logger.Info("machine readable", "category", t, "args", args)
+}
+
+// MachineReadableUi is a UI that only outputs machine-readable output
+// to the given Writer.
+type MachineReadableUi struct {
+	Writer io.Writer
+}
+
+var _ Ui = new(MachineReadableUi)
+
+func (u *MachineReadableUi) Ask(query string) (string, error) {
+	return "", errors.New("machine-readable UI can't ask")
+}
+
+func (u *MachineReadableUi) Detail(message string) {
+	u.Machine("ui", "detail", message)
+}
+
+func (u *MachineReadableUi) Info(message string) {
+	u.Machine("ui", "info", message)
+}
+
+func (u *MachineReadableUi) Output(message string) {
+	u.Machine("ui", "output", message)
+}
+
+func (u *MachineReadableUi) Success(message string) {
+	u.Machine("ui", "success", message)
+}
+
+func (u *MachineReadableUi) Warn(message string) {
+	u.Machine("ui", "warn", message)
+}
+
+func (u *MachineReadableUi) Say(message string) {
+	u.Machine("ui", "say", message)
+}
+
+func (u *MachineReadableUi) Message(message string, opts *Options) {
+	u.Machine("ui", "message", message)
+}
+
+func (u *MachineReadableUi) Error(message string) {
+	u.Machine("ui", "error", message)
+}
+
+// TODO: Do we want to update this to match Vagrant machine style?
+func (u *MachineReadableUi) Machine(category string, args ...string) {
+	now := time.Now().UTC()
+
+	// Determine if we have a target, and set it
+	target := ""
+	commaIdx := strings.Index(category, ",")
+	if commaIdx > -1 {
+		target = category[0:commaIdx]
+		category = category[commaIdx+1:]
+	}
+
+	// Prepare the args
+	for i, v := range args {
+		args[i] = strings.Replace(v, ",", "%!(VAGRANT_COMMA)", -1)
+		args[i] = strings.Replace(args[i], "\r", "\\r", -1)
+		args[i] = strings.Replace(args[i], "\n", "\\n", -1)
+	}
+	argsString := strings.Join(args, ",")
+
+	_, err := fmt.Fprintf(u.Writer, "%d,%s,%s,%s\n", now.Unix(), target, category, argsString)
+	if err != nil {
+		if err == syscall.EPIPE || strings.Contains(err.Error(), "broken pipe") {
+			// Ignore epipe errors because that just means that the file
+			// is probably closed or going to /dev/null or something.
+		} else {
+			panic(err)
+		}
+	}
+}
+
+type NoopUi struct{}
+
+var _ Ui = new(NoopUi)
+
+func (*NoopUi) Ask(string) (string, error) { return "", errors.New("this is a noop ui") }
+func (*NoopUi) Detail(string)              { return }
+func (*NoopUi) Info(string)                { return }
+func (*NoopUi) Error(string)               { return }
+func (*NoopUi) Machine(string, ...string)  { return }
+func (*NoopUi) Message(string, *Options)   { return }
+func (*NoopUi) Output(string)              { return }
+func (*NoopUi) Say(string)                 { return }
+func (*NoopUi) Success(string)             { return }
+func (*NoopUi) Warn(string)                { return }
+
+// ColoredUi is a UI that is colored using terminal colors.
+type ColoredUi struct {
+	Color        UiColor
+	ErrorColor   UiColor
+	SuccessColor UiColor
+	WarnColor    UiColor
+	Ui           Ui
+}
+
+var _ Ui = new(ColoredUi)
+
+func (u *ColoredUi) Ask(query string) (string, error) {
+	return u.Ui.Ask(u.colorize(query, u.Color, true))
+}
+
+func (u *ColoredUi) Detail(message string) {
+	u.Say(message)
+}
+
+func (u *ColoredUi) Info(message string) {
+	u.Say(message)
+}
+
+func (u *ColoredUi) Error(message string) {
+	color := u.ErrorColor
+	if color == 0 {
+		color = UiColorRed
+	}
+
+	u.Ui.Error(u.colorize(message, color, true))
+}
+
+func (u *ColoredUi) Machine(t string, args ...string) {
+	// Don't colorize machine-readable output
+	u.Ui.Machine(t, args...)
+}
+
+func (u *ColoredUi) Message(message string, opts *Options) {
+	u.Ui.Message(u.colorize(message, u.Color, false), opts)
+}
+
+func (u *ColoredUi) Output(message string) {
+	u.Say(message)
+}
+
+func (u *ColoredUi) Say(message string) {
+	u.Ui.Say(u.colorize(message, u.Color, true))
+}
+
+func (u *ColoredUi) Success(message string) {
+	u.Ui.Say(u.colorize(message, u.SuccessColor, true))
+}
+
+func (u *ColoredUi) Warn(message string) {
+	u.Ui.Say(u.colorize(message, u.WarnColor, true))
+}
+
+func (u *ColoredUi) colorize(message string, color UiColor, bold bool) string {
+	if !u.supportsColors() {
+		return message
+	}
+
+	attr := 0
+	if bold {
+		attr = 1
+	}
+
+	return fmt.Sprintf("\033[%d;%dm%s\033[0m", attr, color, message)
+}
+
+func (u *ColoredUi) supportsColors() bool {
+	// Never use colors if we have this environmental variable
+	if os.Getenv("VAGRANT_NO_COLOR") != "" {
+		return false
+	}
+
+	// For now, on non-Windows machine, just assume it does
+	if runtime.GOOS != "windows" {
+		return true
+	}
+
+	// On Windows, if we appear to be in Cygwin, then it does
+	cygwin := os.Getenv("CYGWIN") != "" ||
+		os.Getenv("OSTYPE") == "cygwin" ||
+		os.Getenv("TERM") == "cygwin"
+
+	return cygwin
+}
+
+// TargetedUi is a UI that wraps another UI implementation and modifies
+// the output to indicate a specific target. Specifically, all Say output
+// is prefixed with the target name. Message output is not prefixed but
+// is offset by the length of the target so that output is lined up properly
+// with Say output. Machine-readable output has the proper target set.
+type TargetedUi struct {
+	Target string
+	Ui     Ui
+}
+
+var _ Ui = new(TargetedUi)
+
+func (u *TargetedUi) Ask(query string) (string, error) {
+	return u.Ui.Ask(u.prefixLines(true, query))
+}
+
+func (u *TargetedUi) Detail(message string) {
+	u.Ui.Detail(u.prefixLines(true, message))
+}
+
+func (u *TargetedUi) Info(message string) {
+	u.Ui.Info(u.prefixLines(true, message))
+}
+
+func (u *TargetedUi) Output(message string) {
+	u.Ui.Output(u.prefixLines(true, message))
+}
+
+func (u *TargetedUi) Success(message string) {
+	u.Ui.Success(u.prefixLines(true, message))
+}
+
+func (u *TargetedUi) Warn(message string) {
+	u.Ui.Warn(u.prefixLines(true, message))
+}
+
+func (u *TargetedUi) Say(message string) {
+	u.Ui.Say(u.prefixLines(true, message))
+}
+
+func (u *TargetedUi) Message(message string, opts *Options) {
+	u.Ui.Message(u.prefixLines(false, message), opts)
+}
+
+func (u *TargetedUi) Error(message string) {
+	u.Ui.Error(u.prefixLines(true, message))
+}
+
+func (u *TargetedUi) Machine(t string, args ...string) {
+	// Prefix in the target, then pass through
+	u.Ui.Machine(fmt.Sprintf("%s,%s", u.Target, t), args...)
+}
+
+func (u *TargetedUi) prefixLines(arrow bool, message string) string {
+	arrowText := "==>"
+	if !arrow {
+		arrowText = strings.Repeat(" ", len(arrowText))
+	}
+
+	var result bytes.Buffer
+
+	for _, line := range strings.Split(message, "\n") {
+		result.WriteString(fmt.Sprintf("%s %s: %s\n", arrowText, u.Target, line))
+	}
+
+	return strings.TrimRightFunc(result.String(), unicode.IsSpace)
+}
+
+// TimestampedUi is a UI that wraps another UI implementation and prefixes
+// prefixes each message with an RFC3339 timestamp
+type TimestampedUi struct {
+	Ui Ui
+}
+
+var _ Ui = new(TimestampedUi)
+
+func (u *TimestampedUi) Ask(query string) (string, error) {
+	return u.Ui.Ask(query)
+}
+
+func (u *TimestampedUi) Detail(message string) {
+	u.Ui.Detail(u.timestampLine(message))
+}
+
+func (u *TimestampedUi) Info(message string) {
+	u.Ui.Info(u.timestampLine(message))
+}
+
+func (u *TimestampedUi) Output(message string) {
+	u.Ui.Output(u.timestampLine(message))
+}
+
+func (u *TimestampedUi) Success(message string) {
+	u.Ui.Success(u.timestampLine(message))
+}
+
+func (u *TimestampedUi) Warn(message string) {
+	u.Ui.Warn(u.timestampLine(message))
+}
+
+func (u *TimestampedUi) Say(message string) {
+	u.Ui.Say(u.timestampLine(message))
+}
+
+func (u *TimestampedUi) Message(message string, opts *Options) {
+	u.Ui.Message(u.timestampLine(message), opts)
+}
+
+func (u *TimestampedUi) Error(message string) {
+	u.Ui.Error(u.timestampLine(message))
+}
+
+func (u *TimestampedUi) Machine(message string, args ...string) {
+	u.Ui.Machine(message, args...)
+}
+
+func (u *TimestampedUi) timestampLine(string string) string {
+	return fmt.Sprintf("%v: %v", time.Now().Format(time.RFC3339), string)
+}

ext/go-plugin/vagrant/ui_test.go

@@ -0,0 +1,290 @@
+package vagrant
+
+import (
+	"bytes"
+	"os"
+	"strings"
+	"testing"
+)
+
+// This reads the output from the bytes.Buffer in our test object
+// and then resets the buffer.
+func readWriter(ui *BasicUi) (result string) {
+	buffer := ui.Writer.(*bytes.Buffer)
+	result = buffer.String()
+	buffer.Reset()
+	return
+}
+
+// Reset the input Reader then add some input to it.
+func writeReader(ui *BasicUi, input string) {
+	buffer := ui.Reader.(*bytes.Buffer)
+	buffer.WriteString(input)
+}
+
+func readErrorWriter(ui *BasicUi) (result string) {
+	buffer := ui.ErrorWriter.(*bytes.Buffer)
+	result = buffer.String()
+	buffer.Reset()
+	return
+}
+
+func testUi() *BasicUi {
+	return &BasicUi{
+		Reader:      new(bytes.Buffer),
+		Writer:      new(bytes.Buffer),
+		ErrorWriter: new(bytes.Buffer),
+	}
+}
+
+func TestColoredUi(t *testing.T) {
+	bufferUi := testUi()
+	ui := &ColoredUi{UiColorBlue, UiColorRed, UiColorGreen,
+		UiColorYellow, bufferUi}
+
+	if !ui.supportsColors() {
+		t.Skip("skipping for ui without color support")
+	}
+
+	ui.Say("foo")
+	result := readWriter(bufferUi)
+	if result != "\033[1;34mfoo\033[0m\n" {
+		t.Fatalf("invalid output: %s", result)
+	}
+
+	ui.Message("foo", nil)
+	result = readWriter(bufferUi)
+	if result != "\033[0;34mfoo\033[0m\n" {
+		t.Fatalf("invalid output: %s", result)
+	}
+
+	ui.Error("foo")
+	result = readWriter(bufferUi)
+	if result != "" {
+		t.Fatalf("invalid output: %s", result)
+	}
+
+	result = readErrorWriter(bufferUi)
+	if result != "\033[1;31mfoo\033[0m\n" {
+		t.Fatalf("invalid output: %s", result)
+	}
+}
+
+func TestColoredUi_noColorEnv(t *testing.T) {
+	bufferUi := testUi()
+	ui := &ColoredUi{UiColorBlue, UiColorRed, UiColorGreen,
+		UiColorYellow, bufferUi}
+
+	// Set the env var to get rid of the color
+	oldenv := os.Getenv("VAGRANT_NO_COLOR")
+	os.Setenv("VAGRANT_NO_COLOR", "1")
+	defer os.Setenv("VAGRANT_NO_COLOR", oldenv)
+
+	ui.Say("foo")
+	result := readWriter(bufferUi)
+	if result != "foo\n" {
+		t.Fatalf("invalid output: %s", result)
+	}
+
+	ui.Message("foo", nil)
+	result = readWriter(bufferUi)
+	if result != "foo\n" {
+		t.Fatalf("invalid output: %s", result)
+	}
+
+	ui.Error("foo")
+	result = readErrorWriter(bufferUi)
+	if result != "foo\n" {
+		t.Fatalf("invalid output: %s", result)
+	}
+}
+
+func TestTargetedUi(t *testing.T) {
+	bufferUi := testUi()
+	targetedUi := &TargetedUi{
+		Target: "foo",
+		Ui:     bufferUi,
+	}
+
+	var actual, expected string
+	targetedUi.Say("foo")
+	actual = readWriter(bufferUi)
+	expected = "==> foo: foo\n"
+	if actual != expected {
+		t.Fatalf("bad: %#v", actual)
+	}
+
+	targetedUi.Message("foo", nil)
+	actual = readWriter(bufferUi)
+	expected = "    foo: foo\n"
+	if actual != expected {
+		t.Fatalf("bad: %#v", actual)
+	}
+
+	targetedUi.Error("bar")
+	actual = readErrorWriter(bufferUi)
+	expected = "==> foo: bar\n"
+	if actual != expected {
+		t.Fatalf("bad: %#v", actual)
+	}
+
+	targetedUi.Say("foo\nbar")
+	actual = readWriter(bufferUi)
+	expected = "==> foo: foo\n==> foo: bar\n"
+	if actual != expected {
+		t.Fatalf("bad: %#v", actual)
+	}
+}
+
+func TestColoredUi_ImplUi(t *testing.T) {
+	var raw interface{}
+	raw = &ColoredUi{}
+	if _, ok := raw.(Ui); !ok {
+		t.Fatalf("ColoredUi must implement Ui")
+	}
+}
+
+func TestTargetedUi_ImplUi(t *testing.T) {
+	var raw interface{}
+	raw = &TargetedUi{}
+	if _, ok := raw.(Ui); !ok {
+		t.Fatalf("TargetedUi must implement Ui")
+	}
+}
+
+func TestBasicUi_ImplUi(t *testing.T) {
+	var raw interface{}
+	raw = &BasicUi{}
+	if _, ok := raw.(Ui); !ok {
+		t.Fatalf("BasicUi must implement Ui")
+	}
+}
+
+func TestBasicUi_Error(t *testing.T) {
+	bufferUi := testUi()
+
+	var actual, expected string
+	bufferUi.Error("foo")
+	actual = readErrorWriter(bufferUi)
+	expected = "foo\n"
+	if actual != expected {
+		t.Fatalf("bad: %#v", actual)
+	}
+
+	bufferUi.ErrorWriter = nil
+	bufferUi.Error("5")
+	actual = readWriter(bufferUi)
+	expected = "5\n"
+	if actual != expected {
+		t.Fatalf("bad: %#v", actual)
+	}
+}
+
+func TestBasicUi_Say(t *testing.T) {
+	bufferUi := testUi()
+
+	var actual, expected string
+
+	bufferUi.Say("foo")
+	actual = readWriter(bufferUi)
+	expected = "foo\n"
+	if actual != expected {
+		t.Fatalf("bad: %#v", actual)
+	}
+
+	bufferUi.Say("5")
+	actual = readWriter(bufferUi)
+	expected = "5\n"
+	if actual != expected {
+		t.Fatalf("bad: %#v", actual)
+	}
+}
+
+func TestBasicUi_Ask(t *testing.T) {
+
+	var actual, expected string
+	var err error
+
+	var testCases = []struct {
+		Prompt, Input, Answer string
+	}{
+		{"[c]ontinue or [a]bort", "c\n", "c"},
+		{"[c]ontinue or [a]bort", "c", "c"},
+		// Empty input shouldn't give an error
+		{"Name", "Joe Bloggs\n", "Joe Bloggs"},
+		{"Name", "Joe Bloggs", "Joe Bloggs"},
+		{"Name", "\n", ""},
+	}
+
+	for _, testCase := range testCases {
+		// Because of the internal bufio we can't easily reset the input, so create a new one each time
+		bufferUi := testUi()
+		writeReader(bufferUi, testCase.Input)
+
+		actual, err = bufferUi.Ask(testCase.Prompt)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		if actual != testCase.Answer {
+			t.Fatalf("bad answer: %#v", actual)
+		}
+
+		actual = readWriter(bufferUi)
+		expected = testCase.Prompt + " "
+		if actual != expected {
+			t.Fatalf("bad prompt: %#v", actual)
+		}
+	}
+
+}
+
+func TestMachineReadableUi_ImplUi(t *testing.T) {
+	var raw interface{}
+	raw = &MachineReadableUi{}
+	if _, ok := raw.(Ui); !ok {
+		t.Fatalf("MachineReadableUi must implement Ui")
+	}
+}
+
+func TestMachineReadableUi(t *testing.T) {
+	var data, expected string
+
+	buf := new(bytes.Buffer)
+	ui := &MachineReadableUi{Writer: buf}
+
+	// No target
+	ui.Machine("foo", "bar", "baz")
+	data = strings.SplitN(buf.String(), ",", 2)[1]
+	expected = ",foo,bar,baz\n"
+	if data != expected {
+		t.Fatalf("bad: %s", data)
+	}
+
+	// Target
+	buf.Reset()
+	ui.Machine("mitchellh,foo", "bar", "baz")
+	data = strings.SplitN(buf.String(), ",", 2)[1]
+	expected = "mitchellh,foo,bar,baz\n"
+	if data != expected {
+		t.Fatalf("bad: %s", data)
+	}
+
+	// Commas
+	buf.Reset()
+	ui.Machine("foo", "foo,bar")
+	data = strings.SplitN(buf.String(), ",", 2)[1]
+	expected = ",foo,foo%!(VAGRANT_COMMA)bar\n"
+	if data != expected {
+		t.Fatalf("bad: %s", data)
+	}
+
+	// New lines
+	buf.Reset()
+	ui.Machine("foo", "foo\n")
+	data = strings.SplitN(buf.String(), ",", 2)[1]
+	expected = ",foo,foo\\n\n"
+	if data != expected {
+		t.Fatalf("bad: %#v", data)
+	}
+}

go.mod

@@ -0,0 +1,21 @@
+module github.com/hashicorp/vagrant
+
+require (
+	github.com/LK4D4/joincontext v0.0.0-20171026170139-1724345da6d5
+	github.com/dylanmei/iso8601 v0.1.0 // indirect
+	github.com/dylanmei/winrmtest v0.0.0-20190225150635-99b7fe2fddf1
+	github.com/golang/protobuf v1.3.0
+	github.com/hashicorp/go-hclog v0.8.0
+	github.com/hashicorp/go-plugin v0.0.0-20190220160451-3f118e8ee104
+	github.com/kr/fs v0.1.0 // indirect
+	github.com/masterzen/winrm v0.0.0-20190308153735-1d17eaf15943
+	github.com/mitchellh/iochan v1.0.0
+	github.com/nu7hatch/gouuid v0.0.0-20131221200532-179d4d0c4d8d // indirect
+	github.com/packer-community/winrmcp v0.0.0-20180921211025-c76d91c1e7db
+	github.com/pkg/errors v0.8.1 // indirect
+	github.com/pkg/sftp v1.10.0
+	golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2
+	golang.org/x/net v0.0.0-20190301231341-16b79f2e4e95
+	golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4
+	google.golang.org/grpc v1.19.0
+)

go.sum

@@ -0,0 +1,91 @@
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+google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
+google.golang.org/genproto v0.0.0-20180831171423-11092d34479b h1:lohp5blsw53GBXtLyLNaTXPXS9pJ1tiTw61ZHUoE9Qw=
+google.golang.org/genproto v0.0.0-20180831171423-11092d34479b/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
+google.golang.org/grpc v1.14.0/go.mod h1:yo6s7OP7yaDglbqo1J04qKzAhqBH6lvTonzMVmEdcZw=
+google.golang.org/grpc v1.19.0 h1:cfg4PD8YEdSFnm7qLV4++93WcmhH2nIUhMjhdCvl3j8=
+google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=

lib/vagrant.rb

@@ -1,4 +1,5 @@
 require "log4r"
+require "log4r/logger"
 require "vagrant/util/credential_scrubber"
 # Update the default formatter within the log4r library to ensure
 # sensitive values are being properly scrubbed from logger data
@@ -53,6 +54,8 @@ if ENV["VAGRANT_LOG"] && ENV["VAGRANT_LOG"] != ""
     # rest-client to write using the `<<` operator.
     # See https://github.com/rest-client/rest-client/issues/34#issuecomment-290858
     # for more information
+    Log4r::PatternFormatter::DirectiveTable["l"] =
+      '"[" + ' + Log4r::PatternFormatter::DirectiveTable["l"] + ' + "]"'
     class VagrantLogger < Log4r::Logger
       def << (msg)
         debug(msg.strip)
@@ -61,13 +64,10 @@ if ENV["VAGRANT_LOG"] && ENV["VAGRANT_LOG"] != ""
     logger = VagrantLogger.new("vagrant")
     logger.outputters = Log4r::Outputter.stderr
     logger.level = level
-    base_formatter = Log4r::BasicFormatter.new
-    if ENV["VAGRANT_LOG_TIMESTAMP"]
-      base_formatter = Log4r::PatternFormatter.new(
-        pattern: "%d [%5l] %m",
-        date_pattern: "%F %T"
-      )
-    end
+    base_formatter = Log4r::PatternFormatter.new(
+      pattern: "%d %-7l %C: %m",
+      date_pattern: ENV["VAGRANT_LOG_TIMESTAMP"] ? "%FT%T.%L%z" : " "
+    )
     # Vagrant Cloud gem uses RestClient to make HTTP requests, so
     # log them if debug is enabled and use Vagrants logger
     require 'rest_client'
@@ -118,6 +118,7 @@ module Vagrant
   autoload :Driver,        'vagrant/driver'
   autoload :Environment,   'vagrant/environment'
   autoload :Errors,        'vagrant/errors'
+  autoload :GoPlugin,      'vagrant/go_plugin'
   autoload :Guest,         'vagrant/guest'
   autoload :Host,          'vagrant/host'
   autoload :Machine,       'vagrant/machine'

lib/vagrant/box.rb

@@ -221,5 +221,17 @@ module Vagrant
       "#{@name}-#{@version}-#{@provider}" <=>
       "#{other.name}-#{other.version}-#{other.provider}"
     end
+
+    # @return [String]
+    def to_json(*args)
+      {
+        name: name,
+        provider: provider,
+        version: version,
+        directory: directory.to_s,
+        metadata: metadata,
+        metadata_url: metadata_url
+      }.to_json(*args)
+    end
   end
 end

lib/vagrant/config/v2/dummy_config.rb

@@ -7,6 +7,10 @@ module Vagrant
         def method_missing(name, *args, &block)
           DummyConfig.new
         end
+
+        def to_json(*_)
+          "null"
+        end
       end
     end
   end

lib/vagrant/config/v2/root.rb

@@ -112,6 +112,14 @@ module Vagrant
           @keys              = state["keys"] if state.key?("keys")
           @missing_key_calls = state["missing_key_calls"] if state.key?("missing_key_calls")
         end
+
+        def to_json(*args)
+          Hash[
+            @keys.find_all { |k,v|
+              !k.to_s.start_with?("_")
+            }
+          ].to_json(*args)
+        end
       end
     end
   end

lib/vagrant/environment.rb

@@ -175,6 +175,15 @@ module Vagrant
       # Load any global plugins
       Vagrant::Plugin::Manager.instance.load_plugins(plugins)
 
+      # Load any available go-plugins
+      Util::Experimental.guard_with(:go_plugin) do
+        begin
+          Vagrant::GoPlugin::Manager.instance.globalize!
+        rescue LoadError => err
+          @logger.warn("go plugin support is not available: #{err}")
+        end
+      end
+
       plugins = process_configured_plugins
 
       # Call the hooks that does not require configurations to be loaded
@@ -918,6 +927,26 @@ module Vagrant
       end
     end
 
+    # @return [String]
+    def to_json(*args)
+      {
+        cwd: cwd,
+        data_dir: data_dir,
+        vagrantfile_name: vagrantfile_name,
+        home_path: home_path,
+        local_data_path: local_data_path,
+        tmp_path: tmp_path,
+        aliases_path: aliases_path,
+        boxes_path: boxes_path,
+        gems_path: gems_path,
+        default_private_key_path: default_private_key_path,
+        root_path: root_path,
+        primary_machine_name: primary_machine_name,
+        machine_names: machine_names,
+        active_machines: Hash[active_machines]
+      }.to_json(*args)
+    end
+
     protected
 
     # Attempt to guess the configured provider in use. Will fallback

lib/vagrant/go_plugin.rb

@@ -0,0 +1,26 @@
+module Vagrant
+  autoload :Proto, "vagrant/go_plugin/vagrant_proto/vagrant_services_pb"
+
+  module GoPlugin
+
+    # @return [String]
+    INSTALL_DIRECTORY = Vagrant.user_data_path.join("go-plugins").to_s.freeze
+
+    autoload :CapabilityPlugin, "vagrant/go_plugin/capability_plugin"
+    autoload :ConfigPlugin, "vagrant/go_plugin/config_plugin"
+    autoload :Core, "vagrant/go_plugin/core"
+    autoload :GRPCPlugin, "vagrant/go_plugin/core"
+    autoload :Interface, "vagrant/go_plugin/interface"
+    autoload :Manager, "vagrant/go_plugin/manager"
+    autoload :ProviderPlugin, "vagrant/go_plugin/provider_plugin"
+    autoload :SyncedFolderPlugin, "vagrant/go_plugin/synced_folder_plugin"
+
+    # @return [Interface]
+    def self.interface
+      unless @_interface
+        @_interface = Interface.new
+      end
+      @_interface
+    end
+  end
+end

lib/vagrant/go_plugin/capability_plugin.rb

@@ -0,0 +1,108 @@
+require "vagrant/go_plugin/core"
+
+module Vagrant
+  module GoPlugin
+    # Contains all capability functionality for go-plugin
+    module CapabilityPlugin
+      extend Vagrant::Util::Logger
+
+      # Wrapper class for go-plugin defined capabilities
+      class Capability
+        include GRPCPlugin
+      end
+
+      # Fetch any defined guest capabilites for given plugin and register
+      # capabilities within given plugin class
+      #
+      # @param [Vagrant::Proto::GuestCapabilities::Stub] client Plugin client
+      # @param [Class] plugin_klass Plugin class to register capabilities
+      # @param [Symbol] plugin_type Type of plugin
+      def self.generate_guest_capabilities(client, plugin_klass, plugin_type)
+        logger.debug("checking for guest capabilities in #{plugin_type} plugin #{plugin_klass}")
+        result = client.guest_capabilities(Vagrant::Proto::Empty.new)
+        return if result.capabilities.empty?
+        logger.debug("guest capabilities support detected in #{plugin_type} plugin #{plugin_klass}")
+        result.capabilities.each do |cap|
+          cap_klass = Class.new(Capability).tap do |k|
+            k.define_singleton_method(cap.name) { |machine, *args|
+              response = plugin_client.guest_capability(
+                Vagrant::Proto::GuestCapabilityRequest.new(
+                  machine: JSON.dump(machine), arguments: JSON.dump(args),
+                  capability: Vagrant::Proto::SystemCapability.new(
+                    name: cap.name, platform: cap.platform))).result
+              result = JSON.load(response)
+              if result.is_a?(Hash)
+                result = Vagrant::Util::HashWithIndifferentAccess.new(result)
+              end
+              result
+            }
+          end
+          cap_klass.plugin_client = client
+          plugin_klass.guest_capability(cap.platform.to_sym, cap.name.to_sym) { cap_klass }
+        end
+      end
+
+      # Fetch any defined host capabilites for given plugin and register
+      # capabilities within given plugin class
+      #
+      # @param [Vagrant::Proto::HostCapabilities::Stub] client Plugin client
+      # @param [Class] plugin_klass Plugin class to register capabilities
+      # @param [Symbol] plugin_type Type of plugin
+      def self.generate_host_capabilities(client, plugin_klass, plugin_type)
+        logger.debug("checking for host capabilities in #{plugin_type} plugin #{plugin_klass}")
+        result = client.host_capabilities(Vagrant::Proto::Empty.new)
+        return if result.capabilities.empty?
+        logger.debug("host capabilities support detected in #{plugin_type} plugin #{plugin_klass}")
+        result.capabilities.each do |cap|
+          cap_klass = Class.new(Capability).tap do |k|
+            k.define_singleton_method(cap.name) { |environment, *args|
+              response = plugin_client.host_capability(
+                Vagrant::Proto::HostCapabilityRequest.new(
+                  environment: JSON.dump(environment), arguments: JSON.dump(args),
+                  capability: Vagrant::Proto::SystemCapability.new(
+                    name: cap.name, platform: cap.platform))).result
+              result = JSON.load(response)
+              if result.is_a?(Hash)
+                result = Vagrant::Util::HashWithIndifferentAccess.new(result)
+              end
+              result
+            }
+          end
+          cap_klass.plugin_client = client
+          plugin_klass.host_capability(cap.platform.to_sym, cap.name.to_sym) { cap_klass }
+        end
+      end
+
+      # Fetch any defined provider capabilites for given plugin and register
+      # capabilities within given plugin class
+      #
+      # @param [Vagrant::Proto::ProviderCapabilities::Stub] client Plugin client
+      # @param [Class] plugin_klass Plugin class to register capabilities
+      # @param [Symbol] plugin_type Type of plugin
+      def self.generate_provider_capabilities(client, plugin_klass, plugin_type)
+        logger.debug("checking for provider capabilities in #{plugin_type} plugin #{plugin_klass}")
+        result = client.provider_capabilities(Vagrant::Proto::Empty.new)
+        return if result.capabilities.empty?
+        logger.debug("provider capabilities support detected in #{plugin_type} plugin #{plugin_klass}")
+        result.capabilities.each do |cap|
+          cap_klass = Class.new(Capability).tap do |k|
+            k.define_singleton_method(cap.name) { |machine, *args|
+              response = plugin_client.provider_capability(
+                Vagrant::Proto::ProviderCapabilityRequest.new(
+                  machine: JSON.dump(machine), arguments: JSON.dump(args),
+                  capability: Vagrant::Proto::ProviderCapability.new(
+                    name: cap.name, provider: cap.provider))).result
+              result = JSON.load(response)
+              if result.is_a?(Hash)
+                result = Vagrant::Util::HashWithIndifferentAccess.new(result)
+              end
+              result
+            }
+          end
+          cap_klass.plugin_client = client
+          plugin_klass.provider_capability(cap.provider.to_sym, cap.name.to_sym) { cap_klass }
+        end
+      end
+    end
+  end
+end

lib/vagrant/go_plugin/config_plugin.rb

@@ -0,0 +1,64 @@
+require "vagrant/go_plugin/core"
+
+module Vagrant
+  module GoPlugin
+    # Contains all configuration functionality for go-plugin
+    module ConfigPlugin
+      # Generate configuration for the parent class
+      #
+      # @param [Vagrant::Proto::Config::Stub] client Plugin client
+      # @param [String] parent_name Parent plugin name
+      # @param [Class] parent_klass Parent class to register config
+      # @param [Symbol] parent_type Type of parent class (:provider, :synced_folder, etc)
+      def self.generate_config(client, parent_name, parent_klass, parent_type)
+        config_attrs = client.config_attributes(Vagrant::Proto::Empty.new).items
+        config_klass = Class.new(Config).tap do |c|
+          c.class_eval("def parent_name; '#{parent_name}'; end")
+        end
+        config_klass.plugin_client = client
+        Array(config_attrs).each do |att|
+          config_klass.instance_eval("attr_accessor :#{att}")
+        end
+        parent_klass.config(parent_name, parent_type) { config_klass }
+      end
+
+      # Config plugin class used with go-plugin
+      class Config < Vagrant.plugin("2", :config)
+        include GRPCPlugin
+
+        # Finalize the current configuration
+        def finalize!
+          data = local_data
+          response = plugin_client.config_finalize(Vagrant::Proto::Configuration.new(
+            data: JSON.dump(data)))
+          result = JSON.load(response.data)
+          if result && result.is_a?(Hash)
+            new_data = Vagrant::Util::HashWithIndifferentAccess.new(result)
+            new_data.each do |key, value|
+              next if data[key] == value
+              instance_variable_set("@#{key}", value)
+            end
+          end
+          self
+        end
+
+        # Validate configuration
+        #
+        # @param [Vagrant::Machine] machine Guest machine
+        # @return [Array<String>] list of errors
+        def validate(machine)
+          result = plugin_client.config_validate(Vagrant::Proto::Configuration.new(
+            machine: JSON.dump(machine),
+            data: JSON.dump(local_data)))
+          {parent_name => result.items}
+        end
+
+        # @return [Hash] currently defined instance variables
+        def local_data
+          Vagrant::Util::HashWithIndifferentAccess.
+            new(instance_variables_hash)
+        end
+      end
+    end
+  end
+end

lib/vagrant/go_plugin/core.rb

@@ -0,0 +1,82 @@
+require "ffi"
+
+module Vagrant
+  module GoPlugin
+    # Base module for generic setup of module/class
+    module Core
+      # Loads FFI and core helpers into given module/class
+      def self.included(const)
+        const.class_eval do
+          include Vagrant::Util::Logger
+          extend FFI::Library
+
+          ffi_lib FFI::Platform::LIBC
+          ffi_lib File.expand_path("./go-plugin.so", File.dirname(__FILE__))
+
+          typedef :strptr, :plugin_result
+
+          # stdlib functions
+          if FFI::Platform.windows?
+            attach_function :free, :_free, [:pointer], :void
+          else
+            attach_function :free, [:pointer], :void
+          end
+
+          # Load the result received from the extension. This will load
+          # the JSON result, raise an error if detected, and properly
+          # free the memory associated with the result.
+          def load_result(*args)
+            val, ptr = block_given? ? yield : args
+            FFI::AutoPointer.new(ptr, self.method(:free))
+            begin
+              result = JSON.load(val)
+              if !result.is_a?(Hash)
+                raise TypeError.new "Expected Hash but received `#{result.class}`"
+              end
+              if !result["error"].to_s.empty?
+                raise ArgumentError.new result["error"].to_s
+              end
+              result = result["result"]
+              if result.is_a?(Hash)
+                result = Vagrant::Util::HashWithIndifferentAccess.new(result)
+              end
+              result
+            rescue => e
+              # TODO: Customize to provide formatted output on error
+              raise
+            end
+          end
+        end
+      end
+    end
+
+    # Simple module to load into plugin wrapper classes
+    # to provide expected functionality
+    module GRPCPlugin
+      module ClassMethods
+        def plugin_client
+          @_plugin_client
+        end
+
+        def plugin_client=(c)
+          if @_plugin_client
+            raise ArgumentError, "Plugin client has already been set"
+          end
+          @_plugin_client = c
+        end
+      end
+
+      module InstanceMethods
+        def plugin_client
+          self.class.plugin_client
+        end
+      end
+
+      def self.included(klass)
+        klass.include(Vagrant::Util::Logger)
+        klass.include(InstanceMethods)
+        klass.extend(ClassMethods)
+      end
+    end
+  end
+end

lib/vagrant/go_plugin/interface.rb

@@ -0,0 +1,187 @@
+require "log4r"
+require "vagrant/go_plugin/core"
+
+require "vagrant/go_plugin/vagrant_proto/vagrant_services_pb"
+
+module RubyLogger
+  include Vagrant::Util::Logger
+end
+
+module GRPC
+  extend Vagrant::Util::Logger
+end
+
+
+module Vagrant
+  module GoPlugin
+    # Interface for go-plugin integration
+    class Interface
+      include Core
+
+      # go plugin functions
+      typedef :bool, :enable_logger
+      typedef :bool, :timestamps
+      typedef :string, :log_level
+      typedef :string, :plugin_directory
+
+      attach_function :_setup, :Setup, [:enable_logger, :timestamps, :log_level], :bool
+      attach_function :_teardown, :Teardown, [], :void
+      attach_function :_reset, :Reset, [], :void
+      attach_function :_load_plugins, :LoadPlugins, [:plugin_directory], :bool
+      attach_function :_list_providers, :ListProviders, [], :plugin_result
+      attach_function :_list_synced_folders, :ListSyncedFolders, [], :plugin_result
+
+      def initialize
+        Vagrant::Proto.instance_eval do
+          ::GRPC.extend(Vagrant::Util::Logger)
+        end
+        setup
+      end
+
+      # List of provider plugins currently available
+      #
+      # @return [Hash<String,Hash<Info>>]
+      def list_providers
+        load_result { _list_providers } || {}
+      end
+
+      # List of synced folder plugins currently available
+      #
+      # @return [Hash<String,Hash<Info>>]
+      def list_synced_folders
+        load_result { _list_synced_folders } || {}
+      end
+
+      # Load any plugins found at the given directory
+      #
+      # @param [String, Pathname] path Directory to load
+      def load_plugins(path)
+        logger.debug("loading plugins from path: #{path}")
+        if !File.directory?(path.to_s)
+          raise ArgumentError, "Directory expected for plugin loading"
+        end
+        _load_plugins(path.to_s)
+      end
+
+      # Register all available plugins
+      def register_plugins
+        logger.debug("registering provider plugins")
+        load_providers
+        logger.debug("registering synced folder plugins")
+        load_synced_folders
+      end
+
+      # Load the plugins found at the given directory
+      #
+      # @param [String] plugin_directory Directory containing go-plugins
+      def setup
+        if !@setup
+          @setup = true
+          Kernel.at_exit { Vagrant::GoPlugin.interface.teardown }
+          logger.debug("running go-plugin interface setup")
+          _setup(!Vagrant.log_level.to_s.empty?,
+            !!ENV["VAGRANT_LOG_TIMESTAMP"],
+            Vagrant.log_level.to_s)
+        else
+          logger.warn("go-plugin interface already setup")
+        end
+      end
+
+      def reset
+        logger.debug("running go-plugin interface reset")
+        _reset
+        logger.debug("completed go-plugin interface reset")
+      end
+
+      # Teardown any plugins that may be currently active
+      def teardown
+        logger.debug("starting teardown of go-plugin interface")
+        _teardown
+        logger.debug("teardown of go-plugin interface complete")
+      end
+
+      # @return [Boolean] go plugins have been setup
+      def configured?
+        !!@setup
+      end
+
+      # Load any detected provider plugins
+      def load_providers
+        if !@_providers_loaded
+          @_providers_loaded
+          logger.debug("provider go-plugins have not been loaded... loading")
+          list_providers.each do |p_name, p_details|
+            logger.debug("loading go-plugin provider #{p_name}. details - #{p_details}")
+            client = Vagrant::Proto::Provider::Stub.new(
+              "#{p_details[:network]}://#{p_details[:address]}",
+              :this_channel_is_insecure)
+            # Create new provider class wrapper
+            provider_klass = Class.new(ProviderPlugin::Provider)
+            provider_klass.plugin_client = client
+            # Create new plugin to register the provider
+            plugin_klass = Class.new(Vagrant.plugin("2"))
+            # Define the plugin
+            plugin_klass.class_eval do
+              name "#{p_name} Provider"
+              description p_details[:description]
+            end
+            # Register the provider
+            plugin_klass.provider(p_name.to_sym, priority: p_details.fetch(:priority, 0)) do
+              provider_klass
+            end
+            # Setup any configuration support
+            ConfigPlugin.generate_config(client, p_name, plugin_klass, :provider)
+            # Register any guest capabilities
+            CapabilityPlugin.generate_guest_capabilities(client, plugin_klass, :provider)
+            # Register any host capabilities
+            CapabilityPlugin.generate_host_capabilities(client, plugin_klass, :provider)
+            # Register any provider capabilities
+            CapabilityPlugin.generate_provider_capabilities(client, plugin_klass, :provider)
+            logger.debug("completed loading provider go-plugin #{p_name}")
+            logger.info("loaded go-plugin provider - #{p_name}")
+          end
+        else
+          logger.warn("provider go-plugins have already been loaded. ignoring load request.")
+        end
+      end
+
+      # Load any detected synced folder plugins
+      def load_synced_folders
+        if !@_synced_folders_loaded
+          @_synced_folders_loaded = true
+          logger.debug("synced folder go-plugins have not been loaded... loading")
+          Array(list_synced_folders).each do |f_name, f_details|
+            logger.debug("loading go-plugin synced folder #{f_name}. details - #{f_details}")
+            client = Vagrant::Proto::SyncedFolder::Stub.new(
+              "#{p_details[:network]}://#{p_details[:address]}",
+              :this_channel_is_insecure)
+            # Create new synced folder class wrapper
+            folder_klass = Class.new(SyncedFolderPlugin::SyncedFolder)
+            folder_klass.plugin_client = client
+            # Create new plugin to register the synced folder
+            plugin_klass = Class.new(Vagrant.plugin("2"))
+            # Define the plugin
+            plugin_klass.class_eval do
+              name "#{f_name} Synced Folder"
+              description f_details[:description]
+            end
+            # Register the synced folder
+            plugin_klass.synced_folder(f_name.to_sym, priority: f_details.fetch(:priority, 10)) do
+              folder_klass
+            end
+            # Register any guest capabilities
+            CapabilityPlugin.generate_guest_capabilities(client, plugin_klass, :synced_folder)
+            # Register any host capabilities
+            CapabilityPlugin.generate_host_capabilities(client, plugin_klass, :synced_folder)
+            # Register any provider capabilities
+            CapabilityPlugin.generate_provider_capabilities(client, plugin_klass, :synced_folder)
+            logger.debug("completed loading synced folder go-plugin #{f_name}")
+            logger.info("loaded go-plugin synced folder - #{f_name}")
+          end
+        else
+          logger.warn("synced folder go-plugins have already been loaded. ignoring load request.")
+        end
+      end
+    end
+  end
+end

lib/vagrant/go_plugin/manager.rb

@@ -0,0 +1,87 @@
+require "zip"
+require "vagrant/plugin/state_file"
+
+module Vagrant
+  module GoPlugin
+    class Manager
+      include Util::Logger
+
+      # @return [Manager]
+      def self.instance
+        if !@instance
+          @instance = self.new
+        end
+        @instance
+      end
+
+      # @return [StateFile] user defined plugins
+      attr_reader :user_file
+      # @return [StateFile, nil] project local defined plugins
+      attr_reader :local_file
+
+      def initialize
+        FileUtils.mkdir_p(INSTALL_DIRECTORY)
+        FileUtils.mkdir_p(Vagrant.user_data_path.join("tmp").to_s)
+        @user_file = Plugin::StateFile.new(Vagrant.user_data_path.join("plugins.json"))
+      end
+
+      # Load global plugins
+      def globalize!
+        Dir.glob(File.join(INSTALL_DIRECTORY, "*")).each do |entry|
+          next if !File.directory?(entry)
+          logger.debug("loading go plugins from directory: #{entry}")
+          GoPlugin.interface.load_plugins(entry)
+        end
+        GoPlugin.interface.register_plugins
+      end
+
+      # Load local plugins
+      def localize!
+        raise NotImplementedError
+      end
+
+      # Install a go plugin
+      #
+      # @param [String] plugin_name Name of plugin
+      # @param [String] remote_source Location of plugin for download
+      # @param [Hash] options Currently unused
+      def install_plugin(plugin_name, remote_source, options={})
+        install_dir = File.join(INSTALL_DIRECTORY, plugin_name)
+        FileUtils.mkdir_p(install_dir)
+        Dir.mktmpdir("go-plugin", Vagrant.user_data_path.join("tmp").to_s) do |dir|
+          dest_file = File.join(dir, "plugin.zip")
+          logger.debug("downloading go plugin #{plugin_name} from #{remote_source}")
+          Util::Downloader.new(remote_source, dest_file).download!
+          logger.debug("extracting go plugin #{plugin_name} from #{dest_file}")
+          Zip::File.open(dest_file) do |zfile|
+            zfile.each do |entry|
+              install_path = File.join(install_dir, entry.name)
+              if File.file?(install_path)
+                logger.warn("removing existing plugin path for unpacking - #{install_path}")
+                File.delete(install_path)
+              end
+              entry.extract(install_path)
+              FileUtils.chmod(0755, install_path)
+            end
+          end
+        end
+        user_file.add_go_plugin(plugin_name, source: remote_source)
+      end
+
+      # Uninstall a go plugin
+      #
+      # @param [String] plugin_name Name of plugin
+      # @param [Hash] options Currently unused
+      def uninstall_plugin(plugin_name, options={})
+        plugin_path = File.join(INSTALL_DIRECTORY, plugin_name)
+        if !File.directory?(plugin_path)
+          logger.warn("Plugin directory does not exist for #{plugin_name} - #{plugin_path}")
+        else
+          logger.debug("deleting go plugin from path #{plugin_path}")
+          FileUtils.rm_rf(plugin_path)
+        end
+        user_file.remove_go_plugin(plugin_name)
+      end
+    end
+  end
+end

lib/vagrant/go_plugin/provider_plugin.rb

@@ -0,0 +1,171 @@
+require "vagrant/go_plugin/core"
+
+module Vagrant
+  module GoPlugin
+    module ProviderPlugin
+      # Helper class for wrapping actions in a go-plugin into
+      # something which can be used by Vagrant::Action::Builder
+      class Action
+        include GRPCPlugin
+
+        # @return [String] action name associated to this class
+        def self.action_name
+          @action_name
+        end
+
+        # Set the action name for this class
+        #
+        # @param [String] n action name
+        # @return [String]
+        # @note can only be set once
+        def self.action_name=(n)
+          if @action_name
+            raise ArgumentError.new("Class action name has already been set")
+          end
+          @action_name = n.to_s.dup.freeze
+        end
+
+        def initialize(app, env)
+          @app = app
+        end
+
+        # Run the action
+        def call(env)
+          if env.is_a?(Hash) && !env.is_a?(Vagrant::Util::HashWithIndifferentAccess)
+            env = Vagrant::Util::HashWithIndifferentAccess.new(env)
+          end
+          machine = env.fetch(:machine, {})
+          response = plugin_client.run_action(
+            Vagrant::Proto::ExecuteAction.new(
+              name: self.class.action_name,
+              data: JSON.dump(env),
+              machine: JSON.dump(machine)))
+          result = JSON.load(response.result)
+          if result.is_a?(Hash)
+            result = Vagrant::Util::HashWithIndifferentAccess.new(result)
+            result.each_pair do |k, v|
+              env[k] = v
+            end
+          end
+          @app.call(env)
+        end
+      end
+
+      # Helper class used to provide a wrapper around a go-plugin
+      # provider so that it can be interacted with normally within
+      # Vagrant
+      class Provider < Vagrant.plugin("2", :provider)
+        include GRPCPlugin
+
+        # @return [Vagrant::Machine]
+        attr_reader :machine
+
+        def initialize(machine)
+          @machine = machine
+        end
+
+        # @return [String] name of the provider plugin for this class
+        def name
+          if !@_name
+            @_name = plugin_client.name(Vagrant::Proto::Empty.new).name
+          end
+          @_name
+        end
+
+        # Get callable action by name
+        #
+        # @param [Symbol] name name of the action
+        # @return [Class] callable action class
+        def action(name)
+          result = plugin_client.action(
+            Vagrant::Proto::GenericAction.new(
+              name: name.to_s,
+              machine: JSON.dump(machine)))
+          klasses = result.items.map do |klass_name|
+            if klass_name.start_with?("self::")
+              action_name = klass_name.split("::", 2).last
+              klass = Class.new(Action)
+              klass.plugin_client = plugin_client
+              klass.action_name = action_name
+              klass.class_eval do
+                def self.name
+                  action_name.capitalize.tr("_", "")
+                end
+              end
+              klass
+            else
+              klass_name.split("::").inject(Object) do |memo, const|
+                if memo.const_defined?(const)
+                  memo.const_get(const)
+                else
+                  raise NameError, "Unknown action class `#{klass_name}`"
+                end
+              end
+            end
+          end
+          Vagrant::Action::Builder.new.tap do |builder|
+            klasses.each do |action_class|
+              builder.use action_class
+            end
+          end
+        end
+
+        # Execute capability with given name
+        #
+        # @param [Symbol] cap_name Name of the capability
+        # @return [Object]
+        def capability(cap_name, *args)
+          r = plugin_client.provider_capability(
+            Vagrant::Proto::ProviderCapabilityRequest.new(
+              capability: Vagrant::Proto::ProviderCapability.new(
+                name: cap_name.to_s,
+                provider: name
+              ),
+              machine: JSON.dump(machine),
+              arguments: JSON.dump(args)
+            )
+          )
+          result = JSON.load(r.result)
+          if result.is_a?(Hash)
+            result = Vagrant::Util::HashWithIndifferentAccess.new(result)
+          end
+          result
+        end
+
+        # @return [Boolean] provider is installed
+        def is_installed?
+          plugin_client.is_installed(Vagrant::Proto::Machine.new(
+            machine: JSON.dump(machine))).result
+        end
+
+        # @return [Boolean] provider is usable
+        def is_usable?
+          plugin_client.is_usable(Vagrant::Proto::Machine.new(
+            machine: JSON.dump(machine))).result
+        end
+
+        # @return [nil]
+        def machine_id_changed
+          plugin_client.machine_id_changed(Vagrant::Proto::Machine.new(
+            machine: JSON.dump(machine)))
+          nil
+        end
+
+        # @return [Hash] SSH information
+        def ssh_info
+          result = plugin_client.ssh_info(Vagrant::Proto::Machine.new(
+            machine: JSON.dump(machine))).to_hash
+          Vagrant::Util::HashWithIndifferentAccess.new(result)
+        end
+
+        # @return [Vagrant::MachineState]
+        def state
+          result = plugin_client.state(Vagrant::Proto::Machine.new(
+            machine: JSON.dump(machine)))
+          Vagrant::MachineState.new(result.id,
+            result.short_description, result.long_description)
+        end
+      end
+    end
+  end
+end

lib/vagrant/go_plugin/synced_folder_plugin.rb

@@ -0,0 +1,89 @@
+require "vagrant/go_plugin/core"
+
+module Vagrant
+  module GoPlugin
+    # Contains all synced folder functionality for go-plugin
+    module SyncedFolderPlugin
+
+      # Helper class used to provide a wrapper around a go-plugin
+      # synced folder so that it can be interacted with normally
+      # within Vagrant
+      class SyncedFolder < Vagrant.plugin("2", :synced_folder)
+        include GRPCPlugin
+
+        # Cleanup synced folders
+        #
+        # @param [Vagrant::Machine] machine Vagrant guest
+        # @param [Hash] opts Folder options
+        def cleanup(machine, opts)
+          plugin_client.cleanup(
+            Vagrant::Proto::SyncedFolders.new(
+              machine: JSON.dump(machine),
+              options: JSON.dump(opts),
+              folders: JSON.dump({})))
+          nil
+        end
+
+        # Disable synced folders
+        #
+        # @param [Vagrant::Machine] machine Vagrant guest
+        # @param [Hash] folders Folders to enable
+        # @param [Hash] opts Folder options
+        def disable(machine, folders, opts)
+          plugin_client.disable(
+            Vagrant::Proto::SyncedFolders.new(
+              machine: JSON.dump(machine),
+              folders: JSON.dump(folders),
+              options: JSON.dump(opts)))
+          nil
+        end
+
+        # Enable synced folders
+        #
+        # @param [Vagrant::Machine] machine Vagrant guest
+        # @param [Hash] folders Folders to enable
+        # @param [Hash] opts Folder options
+        def enable(machine, folders, opts)
+          plugin_client.enable(
+            Vagrant::Proto::SyncedFolders.new(
+              machine: JSON.dump(machine),
+              folders: JSON.dump(folders),
+              options: JSON.dump(options)))
+          nil
+        end
+
+        # Prepare synced folders
+        #
+        # @param [Vagrant::Machine] machine Vagrant guest
+        # @param [Hash] folders Folders to enable
+        # @param [Hash] opts Folder options
+        def prepare(machine, folders, opts)
+          plugin_client.prepare(
+            Vagrant::Proto::SyncedFolders.new(
+              machine: JSON.dump(machine),
+              folders: JSON.dump(folders),
+              options: JSON.dump(options)))
+          nil
+        end
+
+        # Check if plugin is usable
+        #
+        # @param [Vagrant::Machine] machine Vagrant guest
+        # @return [Boolean]
+        def usable?(machine, raise_error=false)
+          plugin_client.is_usable(
+            Vagrant::Proto::Machine.new(
+              machine: JSON.dump(machine))).result
+        end
+
+        # @return [String]
+        def name
+          if !@_name
+            @_name = plugin_client.name(Vagrant::Proto::Empty.new).name
+          end
+          @_name
+        end
+      end
+    end
+  end
+end

lib/vagrant/go_plugin/vagrant_proto/vagrant_pb.rb

@@ -0,0 +1,122 @@
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: vagrant.proto
+
+require 'google/protobuf'
+
+Google::Protobuf::DescriptorPool.generated_pool.build do
+  add_file("vagrant.proto", :syntax => :proto3) do
+    add_message "vagrant.proto.Empty" do
+    end
+    add_message "vagrant.proto.Machine" do
+      optional :machine, :string, 1
+    end
+    add_message "vagrant.proto.Valid" do
+      optional :result, :bool, 1
+    end
+    add_message "vagrant.proto.Identifier" do
+      optional :name, :string, 1
+    end
+    add_message "vagrant.proto.PluginInfo" do
+      optional :description, :string, 1
+      optional :priority, :int64, 2
+    end
+    add_message "vagrant.proto.Content" do
+      optional :target, :string, 1
+      optional :value, :string, 2
+    end
+    add_message "vagrant.proto.WriteResponse" do
+      optional :length, :int32, 1
+    end
+    add_message "vagrant.proto.SystemCapability" do
+      optional :name, :string, 1
+      optional :platform, :string, 2
+    end
+    add_message "vagrant.proto.ProviderCapability" do
+      optional :name, :string, 1
+      optional :provider, :string, 2
+    end
+    add_message "vagrant.proto.SystemCapabilityList" do
+      repeated :capabilities, :message, 1, "vagrant.proto.SystemCapability"
+    end
+    add_message "vagrant.proto.ProviderCapabilityList" do
+      repeated :capabilities, :message, 1, "vagrant.proto.ProviderCapability"
+    end
+    add_message "vagrant.proto.GenericResponse" do
+      optional :result, :string, 1
+    end
+    add_message "vagrant.proto.GuestCapabilityRequest" do
+      optional :capability, :message, 1, "vagrant.proto.SystemCapability"
+      optional :machine, :string, 2
+      optional :arguments, :string, 3
+    end
+    add_message "vagrant.proto.HostCapabilityRequest" do
+      optional :capability, :message, 1, "vagrant.proto.SystemCapability"
+      optional :environment, :string, 2
+      optional :arguments, :string, 3
+    end
+    add_message "vagrant.proto.ProviderCapabilityRequest" do
+      optional :capability, :message, 1, "vagrant.proto.ProviderCapability"
+      optional :machine, :string, 2
+      optional :arguments, :string, 3
+    end
+    add_message "vagrant.proto.Configuration" do
+      optional :data, :string, 1
+      optional :machine, :string, 2
+    end
+    add_message "vagrant.proto.ListResponse" do
+      repeated :items, :string, 1
+    end
+    add_message "vagrant.proto.SyncedFolders" do
+      optional :machine, :string, 1
+      optional :folders, :string, 2
+      optional :options, :string, 3
+    end
+    add_message "vagrant.proto.GenericAction" do
+      optional :name, :string, 1
+      optional :machine, :string, 2
+    end
+    add_message "vagrant.proto.ExecuteAction" do
+      optional :name, :string, 1
+      optional :data, :string, 2
+      optional :machine, :string, 3
+    end
+    add_message "vagrant.proto.MachineSshInfo" do
+      optional :host, :string, 1
+      optional :port, :int64, 2
+      optional :private_key_path, :string, 3
+      optional :username, :string, 4
+    end
+    add_message "vagrant.proto.MachineState" do
+      optional :id, :string, 1
+      optional :short_description, :string, 2
+      optional :long_description, :string, 3
+    end
+  end
+end
+
+module Vagrant
+  module Proto
+    Empty = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.Empty").msgclass
+    Machine = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.Machine").msgclass
+    Valid = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.Valid").msgclass
+    Identifier = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.Identifier").msgclass
+    PluginInfo = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.PluginInfo").msgclass
+    Content = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.Content").msgclass
+    WriteResponse = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.WriteResponse").msgclass
+    SystemCapability = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.SystemCapability").msgclass
+    ProviderCapability = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.ProviderCapability").msgclass
+    SystemCapabilityList = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.SystemCapabilityList").msgclass
+    ProviderCapabilityList = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.ProviderCapabilityList").msgclass
+    GenericResponse = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.GenericResponse").msgclass
+    GuestCapabilityRequest = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.GuestCapabilityRequest").msgclass
+    HostCapabilityRequest = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.HostCapabilityRequest").msgclass
+    ProviderCapabilityRequest = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.ProviderCapabilityRequest").msgclass
+    Configuration = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.Configuration").msgclass
+    ListResponse = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.ListResponse").msgclass
+    SyncedFolders = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.SyncedFolders").msgclass
+    GenericAction = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.GenericAction").msgclass
+    ExecuteAction = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.ExecuteAction").msgclass
+    MachineSshInfo = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.MachineSshInfo").msgclass
+    MachineState = Google::Protobuf::DescriptorPool.generated_pool.lookup("vagrant.proto.MachineState").msgclass
+  end
+end

lib/vagrant/go_plugin/vagrant_proto/vagrant_services_pb.rb

@@ -0,0 +1,223 @@
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# Source: vagrant.proto for package 'vagrant.proto'
+
+require 'grpc'
+require_relative 'vagrant_pb'
+
+module Vagrant
+  module Proto
+    module IO
+      class Service
+
+        include GRPC::GenericService
+
+        self.marshal_class_method = :encode
+        self.unmarshal_class_method = :decode
+        self.service_name = 'vagrant.proto.IO'
+
+        rpc :Read, Identifier, Content
+        rpc :Write, Content, WriteResponse
+      end
+
+      Stub = Service.rpc_stub_class
+    end
+    module GuestCapabilities
+      class Service
+
+        include GRPC::GenericService
+
+        self.marshal_class_method = :encode
+        self.unmarshal_class_method = :decode
+        self.service_name = 'vagrant.proto.GuestCapabilities'
+
+        rpc :GuestCapabilities, Empty, SystemCapabilityList
+        rpc :GuestCapability, GuestCapabilityRequest, GenericResponse
+        # IO helpers for streaming (copied from Stream service)
+        rpc :Read, Identifier, Content
+        rpc :Write, Content, WriteResponse
+      end
+
+      Stub = Service.rpc_stub_class
+    end
+    module HostCapabilities
+      class Service
+
+        include GRPC::GenericService
+
+        self.marshal_class_method = :encode
+        self.unmarshal_class_method = :decode
+        self.service_name = 'vagrant.proto.HostCapabilities'
+
+        rpc :HostCapabilities, Empty, SystemCapabilityList
+        rpc :HostCapability, HostCapabilityRequest, GenericResponse
+        # IO helpers for streaming (copied from Stream service)
+        rpc :Read, Identifier, Content
+        rpc :Write, Content, WriteResponse
+      end
+
+      Stub = Service.rpc_stub_class
+    end
+    module ProviderCapabilities
+      class Service
+
+        include GRPC::GenericService
+
+        self.marshal_class_method = :encode
+        self.unmarshal_class_method = :decode
+        self.service_name = 'vagrant.proto.ProviderCapabilities'
+
+        rpc :ProviderCapabilities, Empty, ProviderCapabilityList
+        rpc :ProviderCapability, ProviderCapabilityRequest, GenericResponse
+        # IO helpers for streaming (copied from Stream service)
+        rpc :Read, Identifier, Content
+        rpc :Write, Content, WriteResponse
+      end
+
+      Stub = Service.rpc_stub_class
+    end
+    module Config
+      class Service
+
+        include GRPC::GenericService
+
+        self.marshal_class_method = :encode
+        self.unmarshal_class_method = :decode
+        self.service_name = 'vagrant.proto.Config'
+
+        rpc :ConfigAttributes, Empty, ListResponse
+        rpc :ConfigLoad, Configuration, Configuration
+        rpc :ConfigValidate, Configuration, ListResponse
+        rpc :ConfigFinalize, Configuration, Configuration
+        # IO helpers for streaming (copied from Stream service)
+        rpc :Read, Identifier, Content
+        rpc :Write, Content, WriteResponse
+      end
+
+      Stub = Service.rpc_stub_class
+    end
+    module SyncedFolder
+      class Service
+
+        include GRPC::GenericService
+
+        self.marshal_class_method = :encode
+        self.unmarshal_class_method = :decode
+        self.service_name = 'vagrant.proto.SyncedFolder'
+
+        rpc :Cleanup, SyncedFolders, Empty
+        rpc :Disable, SyncedFolders, Empty
+        rpc :Enable, SyncedFolders, Empty
+        rpc :Info, Empty, PluginInfo
+        rpc :IsUsable, Machine, Valid
+        rpc :Name, Empty, Identifier
+        rpc :Prepare, SyncedFolders, Empty
+        # IO helpers for streaming (copied from Stream service)
+        rpc :Read, Identifier, Content
+        rpc :Write, Content, WriteResponse
+        # Guest capabilities helpers (copied from GuestCapabilities service)
+        rpc :GuestCapabilities, Empty, SystemCapabilityList
+        rpc :GuestCapability, GuestCapabilityRequest, GenericResponse
+        # Host capabilities helpers (copied from GuestCapabilities service)
+        rpc :HostCapabilities, Empty, SystemCapabilityList
+        rpc :HostCapability, HostCapabilityRequest, GenericResponse
+      end
+
+      Stub = Service.rpc_stub_class
+    end
+    module Provider
+      class Service
+
+        include GRPC::GenericService
+
+        self.marshal_class_method = :encode
+        self.unmarshal_class_method = :decode
+        self.service_name = 'vagrant.proto.Provider'
+
+        rpc :Action, GenericAction, ListResponse
+        rpc :Info, Empty, PluginInfo
+        rpc :IsInstalled, Machine, Valid
+        rpc :IsUsable, Machine, Valid
+        rpc :MachineIdChanged, Machine, Machine
+        rpc :Name, Empty, Identifier
+        rpc :RunAction, ExecuteAction, GenericResponse
+        rpc :SshInfo, Machine, MachineSshInfo
+        rpc :State, Machine, MachineState
+        # IO helpers for streaming (copied from Stream service)
+        rpc :Read, Identifier, Content
+        rpc :Write, Content, WriteResponse
+        # Config helpers (copied from Config service)
+        rpc :ConfigAttributes, Empty, ListResponse
+        rpc :ConfigLoad, Configuration, Configuration
+        rpc :ConfigValidate, Configuration, ListResponse
+        rpc :ConfigFinalize, Configuration, Configuration
+        # Guest capabilities helpers (copied from GuestCapabilities service)
+        rpc :GuestCapabilities, Empty, SystemCapabilityList
+        rpc :GuestCapability, GuestCapabilityRequest, GenericResponse
+        # Host capabilities helpers (copied from HostCapabilities service)
+        rpc :HostCapabilities, Empty, SystemCapabilityList
+        rpc :HostCapability, HostCapabilityRequest, GenericResponse
+        # Provider capabilities helpers (copied from ProviderCapabilities service)
+        rpc :ProviderCapabilities, Empty, ProviderCapabilityList
+        rpc :ProviderCapability, ProviderCapabilityRequest, GenericResponse
+      end
+
+      Stub = Service.rpc_stub_class
+    end
+  end
+end
+
+require 'logger'
+
+# DebugIsTruncated extends the default Logger to truncate debug messages
+class DebugIsTruncated < Logger
+  def debug(s)
+    super(truncate(s, 1024))
+  end
+
+  # Truncates a given +text+ after a given <tt>length</tt> if +text+ is longer than <tt>length</tt>:
+  #
+  #   'Once upon a time in a world far far away'.truncate(27)
+  #   # => "Once upon a time in a wo..."
+  #
+  # Pass a string or regexp <tt>:separator</tt> to truncate +text+ at a natural break:
+  #
+  #   'Once upon a time in a world far far away'.truncate(27, separator: ' ')
+  #   # => "Once upon a time in a..."
+  #
+  #   'Once upon a time in a world far far away'.truncate(27, separator: /\s/)
+  #   # => "Once upon a time in a..."
+  #
+  # The last characters will be replaced with the <tt>:omission</tt> string (defaults to "...")
+  # for a total length not exceeding <tt>length</tt>:
+  #
+  #   'And they found that many people were sleeping better.'.truncate(25, omission: '... (continued)')
+  #   # => "And they f... (continued)"
+  def truncate(s, truncate_at, options = {})
+    return s unless s.length > truncate_at
+    omission = options[:omission] || '...'
+    with_extra_room = truncate_at - omission.length
+    stop = \
+      if options[:separator]
+        rindex(options[:separator], with_extra_room) || with_extra_room
+      else
+        with_extra_room
+      end
+    "#{s[0, stop]}#{omission}"
+  end
+end
+
+# RubyLogger defines a logger for gRPC based on the standard ruby logger.
+module RubyLogger
+  def logger
+    LOGGER
+  end
+
+  LOGGER = DebugIsTruncated.new(STDOUT)
+  LOGGER.level = Logger::DEBUG
+end
+
+# GRPC is the general RPC module
+module GRPC
+  # Inject the noop #logger if no module-level logger method has been injected.
+  extend RubyLogger
+end

lib/vagrant/machine.rb

@@ -578,6 +578,20 @@ module Vagrant
       end
     end
 
+    # @return [String]
+    def to_json(*args)
+      {
+        box: box,
+        config: config,
+        data_dir: data_dir,
+        environment: env,
+        id: id,
+        name: name,
+        provider_config: provider_config,
+        provider_name: provider_name
+      }.to_json(*args)
+    end
+
     protected
 
     # Returns the path to the file that stores the UID.

lib/vagrant/plugin/state_file.rb

@@ -28,6 +28,7 @@ module Vagrant
 
         @data["version"] ||= "1"
         @data["installed"] ||= {}
+        @data["go_plugin"] ||= {}
       end
 
       # Add a plugin that is installed to the state file.
@@ -47,6 +48,43 @@ module Vagrant
         save!
       end
 
+      # Add a go plugin that is installed to the state file
+      #
+      # @param [String, Symbol] name Plugin name
+      def add_go_plugin(name, **opts)
+        @data["go_plugin"][name] = {
+          "source" => opts[:source]
+        }
+
+        save!
+      end
+
+      # Remove a go plugin that is installed from the state file
+      #
+      # @param [String, Symbol] name Name of the plugin
+      def remove_go_plugin(name)
+        @data["go_plugin"].delete(name.to_s)
+
+        save!
+      end
+
+      # Check if go plugin is installed from the state file
+      #
+      # @param [String, Symbol] name Plugin name
+      # @return [Boolean]
+      def has_go_plugin?(name)
+        @data["go_plugin"].key?(name.to_s)
+      end
+
+      # This returns a hash of installed go plugins according to the state
+      # file. Note that this may _not_ directly match over to actually
+      # installed plugins
+      #
+      # @return [Hash]
+      def installed_go_plugins
+        @data["go_plugin"]
+      end
+
       # Adds a RubyGems index source to look up gems.
       #
       # @param [String] url URL of the source.

lib/vagrant/plugin/v2/config.rb

@@ -138,6 +138,12 @@ module Vagrant
           @__finalized = true
         end
       end
+
+      class Set < ::Set
+        def to_json(*args)
+          self.to_a.to_json(*args)
+        end
+      end
     end
   end
 end

lib/vagrant/util.rb

@@ -8,7 +8,9 @@ module Vagrant
     autoload :DeepMerge,                 'vagrant/util/deep_merge'
     autoload :Env,                       'vagrant/util/env'
     autoload :HashWithIndifferentAccess, 'vagrant/util/hash_with_indifferent_access'
+    autoload :Experimental,              'vagrant/util/experimental'
     autoload :GuestInspection,           'vagrant/util/guest_inspection'
+    autoload :Logger,                    'vagrant/util/logger'
     autoload :LoggingFormatter,          'vagrant/util/logging_formatter'
     autoload :Platform,                  'vagrant/util/platform'
     autoload :Retryable,                 'vagrant/util/retryable'

lib/vagrant/util/hash_with_indifferent_access.rb

@@ -14,6 +14,9 @@ module Vagrant
         super(&block)
 
         hash.each do |key, value|
+          if value.is_a?(Hash) && !value.is_a?(self.class)
+            value = self.class.new(value)
+          end
           self[convert_key(key)] = value
         end
       end

lib/vagrant/util/logger.rb

@@ -0,0 +1,22 @@
+require "log4r"
+
+module Vagrant
+  module Util
+    # Adds a logger method which provides automatically
+    # namespaced logger instance
+    module Logger
+
+      # @return [Log4r::Logger]
+      def logger
+        if !@_logger
+          name = (self.is_a?(Module) ? self : self.class).name.downcase
+          if !name.start_with?("vagrant")
+            name = "vagrant::root::#{name}"
+          end
+          @_logger = Log4r::Logger.new(name)
+        end
+        @_logger
+      end
+    end
+  end
+end

plugins/commands/plugin/action.rb

@@ -74,6 +74,23 @@ module VagrantPlugins
       autoload :RepairPluginsLocal, action_root.join("repair_plugins")
       autoload :UninstallPlugin, action_root.join("uninstall_plugin")
       autoload :UpdateGems, action_root.join("update_gems")
+
+      Vagrant::Util::Experimental.guard_with(:go_plugin) do
+        autoload :UninstallGoPlugin, action_root.join("uninstall_go_plugin")
+        autoload :InstallGoPlugin, action_root.join("install_go_plugin")
+
+        def self.action_go_install
+          Vagrant::Action::Builder.new.tap do |b|
+            b.use InstallGoPlugin
+          end
+        end
+
+        def self.action_go_uninstall
+          Vagrant::Action::Builder.new.tap do |b|
+            b.use UninstallGoPlugin
+          end
+        end
+      end
     end
   end
 end

plugins/commands/plugin/action/install_go_plugin.rb

@@ -0,0 +1,35 @@
+require "log4r"
+require "vagrant/go_plugin/manager"
+
+module VagrantPlugins
+  module CommandPlugin
+    module Action
+      class InstallGoPlugin
+        def initialize(app, env)
+          @app    = app
+          @logger = Log4r::Logger.new("vagrant::plugins::plugincommand::installgoplugin")
+        end
+
+        def call(env)
+          plugin_name = env[:plugin_name]
+          plugin_source = env[:plugin_source]
+
+          manager = Vagrant::GoPlugin::Manager.instance
+
+          env[:ui].info(I18n.t("vagrant.commands.plugin.installing",
+            name: plugin_name))
+
+          manager.install_plugin(plugin_name, plugin_source)
+
+          # Tell the user
+          env[:ui].success(I18n.t("vagrant.commands.plugin.installed",
+                                  name: plugin_name,
+                                  version: plugin_source))
+
+          # Continue
+          @app.call(env)
+        end
+      end
+    end
+  end
+end

plugins/commands/plugin/action/uninstall_go_plugin.rb

@@ -0,0 +1,22 @@
+module VagrantPlugins
+  module CommandPlugin
+    module Action
+      class UninstallGoPlugin
+        def initialize(app, env)
+          @app = app
+        end
+
+        def call(env)
+          # Remove it!
+          env[:ui].info(I18n.t("vagrant.commands.plugin.uninstalling",
+            name: env[:plugin_name]))
+
+          manager = Vagrant::GoPlugin::Manager.instance
+          manager.uninstall_plugin(env[:plugin_name])
+
+          @app.call(env)
+        end
+      end
+    end
+  end
+end

plugins/commands/plugin/command/go_install.rb

@@ -0,0 +1,43 @@
+require 'optparse'
+
+require_relative "base"
+
+module VagrantPlugins
+  module CommandPlugin
+    module Command
+      class GoInstall < Base
+
+        def execute
+          options = { verbose: false }
+
+          opts = OptionParser.new do |o|
+            o.banner = "Usage: vagrant plugin goinstall <name> <source>"
+            o.separator ""
+
+            o.on("--verbose", "Enable verbose output for plugin installation") do |v|
+              options[:verbose] = v
+            end
+          end
+
+          # Parse the options
+          argv = parse_options(opts)
+          return if !argv
+
+          if argv.length != 2
+            raise Vagrant::Errors::CLIInvalidUsage, help: opts.help.chomp
+          end
+
+          plugin_name, plugin_source = argv
+
+          action(Action.action_go_install,
+            plugin_name: plugin_name,
+            plugin_source: plugin_source
+          )
+
+          # Success, exit status 0
+          0
+        end
+      end
+    end
+  end
+end

plugins/commands/plugin/command/go_uninstall.rb

@@ -0,0 +1,31 @@
+require 'optparse'
+
+require_relative "base"
+
+module VagrantPlugins
+  module CommandPlugin
+    module Command
+      class GoUninstall < Base
+        def execute
+          options = {}
+          opts = OptionParser.new do |o|
+            o.banner = "Usage: vagrant plugin gouninstall <name> [<name2> <name3> ...] [-h]"
+          end
+
+          # Parse the options
+          argv = parse_options(opts)
+          return if !argv
+          raise Vagrant::Errors::CLIInvalidUsage, help: opts.help.chomp if argv.length < 1
+
+          # Uninstall the plugins
+          argv.each do |entry|
+            action(Action.action_go_uninstall, plugin_name: entry)
+          end
+
+          # Success, exit status 0
+          0
+        end
+      end
+    end
+  end
+end

plugins/commands/plugin/command/root.rb

@@ -48,6 +48,18 @@ module VagrantPlugins
             require_relative "uninstall"
             Uninstall
           end
+
+          Vagrant::Util::Experimental.guard_with(:go_plugin) do
+            @subcommands.register(:goinstall) do
+              require_relative "go_install"
+              GoInstall
+            end
+
+            @subcommands.register(:gouninstall) do
+              require_relative "go_uninstall"
+              GoUninstall
+            end
+          end
         end
 
         def execute

test/unit/vagrant/cli_test.rb

@@ -30,6 +30,9 @@ describe Vagrant::CLI do
   describe "#execute" do
     let(:triggers) { double("triggers") }
 
+    before { allow(Vagrant::Util::Experimental).to receive(:feature_enabled?) }
+
+
     it "invokes help and exits with 1 if invalid command" do
       subject = described_class.new(["i-dont-exist"], env)
       expect(subject).to receive(:help).once
@@ -59,7 +62,7 @@ describe Vagrant::CLI do
 
     it "fires triggers, if enabled" do
       allow(Vagrant::Util::Experimental).to receive(:feature_enabled?).
-        with("typed_triggers").and_return("true")
+        with("typed_triggers").and_return(true)
       allow(triggers).to receive(:fire_triggers)
 
       commands[:destroy] = [command_lambda("destroy", 42), {}]
@@ -76,7 +79,7 @@ describe Vagrant::CLI do
 
     it "does not fire triggers if disabled" do
       allow(Vagrant::Util::Experimental).to receive(:feature_enabled?).
-        with("typed_triggers").and_return("false")
+        with("typed_triggers").and_return(false)
 
       commands[:destroy] = [command_lambda("destroy", 42), {}]
 

test/unit/vagrant/go_plugin/capability_plugin_test.rb

@@ -0,0 +1,215 @@
+require_relative "../../base"
+
+describe Vagrant::GoPlugin::CapabilityPlugin do
+  let(:client) { double("client") }
+
+  describe Vagrant::GoPlugin::CapabilityPlugin::Capability do
+    it "should be a GRPCPlugin" do
+      expect(described_class.ancestors).to include(Vagrant::GoPlugin::GRPCPlugin)
+    end
+  end
+
+  describe ".generate_guest_capabilities" do
+    let(:caps) {
+      [{platform: "dummy", name: "stub_cap"},
+        {platform: "dummy", name: "other_cap"}]}
+    let(:cap_response) {
+      Vagrant::Proto::SystemCapabilityList.new(
+        capabilities: caps.map { |i|
+          Vagrant::Proto::SystemCapability.new(i)})}
+    let(:plugin_klass) { double("plugin_klass") }
+    let(:plugin_type) { :testing }
+
+
+    before do
+      allow(client).to receive(:guest_capabilities).
+        and_return(cap_response)
+      allow(plugin_klass).to receive(:guest_capability)
+    end
+
+    it "should generate two new capability classes" do
+      expect(Class).to receive(:new).twice.
+        with(Vagrant::GoPlugin::CapabilityPlugin::Capability).
+        and_call_original
+      described_class.generate_guest_capabilities(client, plugin_klass, plugin_type)
+    end
+
+    it "should create capability name methods" do
+      c1 = Class.new(Vagrant::GoPlugin::CapabilityPlugin::Capability)
+      c2 = Class.new(Vagrant::GoPlugin::CapabilityPlugin::Capability)
+      expect(Class).to receive(:new).and_return(c1)
+      expect(Class).to receive(:new).and_return(c2)
+      described_class.generate_guest_capabilities(client, plugin_klass, plugin_type)
+      expect(c1).to respond_to(:stub_cap)
+      expect(c2).to respond_to(:other_cap)
+    end
+
+    it "should register guest capability" do
+      expect(plugin_klass).to receive(:guest_capability).with(:dummy, :stub_cap)
+      expect(plugin_klass).to receive(:guest_capability).with(:dummy, :other_cap)
+      described_class.generate_guest_capabilities(client, plugin_klass, plugin_type)
+    end
+
+    context "generated capability" do
+      let(:cap_class) { Class.new(Vagrant::GoPlugin::CapabilityPlugin::Capability) }
+      let(:response) { double(result: result) }
+      let(:result) { nil }
+
+      before {
+        expect(Class).to receive(:new).and_return(cap_class)
+        allow(Class).to receive(:new).and_call_original
+        described_class.generate_guest_capabilities(client, plugin_klass, plugin_type)
+      }
+
+      it "should call guest_capability on the plugin client" do
+        expect(client).to receive(:guest_capability).and_return(response)
+        cap_class.stub_cap(nil, nil)
+      end
+
+      context "when result is a hash" do
+        let(:result) { "{}" }
+
+        it "should convert hash to hash with indifferent access" do
+          expect(client).to receive(:guest_capability).and_return(response)
+          expect(cap_class.stub_cap(nil, nil)).to be_a(Vagrant::Util::HashWithIndifferentAccess)
+        end
+      end
+    end
+  end
+
+  describe ".generate_host_capabilities" do
+    let(:caps) {
+      [{platform: "dummy", name: "stub_cap"},
+        {platform: "dummy", name: "other_cap"}]}
+    let(:cap_response) {
+      Vagrant::Proto::SystemCapabilityList.new(
+        capabilities: caps.map { |i|
+          Vagrant::Proto::SystemCapability.new(i)})}
+    let(:plugin_klass) { double("plugin_klass") }
+    let(:plugin_type) { :testing }
+
+
+    before do
+      allow(client).to receive(:host_capabilities).
+        and_return(cap_response)
+      allow(plugin_klass).to receive(:host_capability)
+    end
+
+    it "should generate two new capability classes" do
+      expect(Class).to receive(:new).twice.
+        with(Vagrant::GoPlugin::CapabilityPlugin::Capability).
+        and_call_original
+      described_class.generate_host_capabilities(client, plugin_klass, plugin_type)
+    end
+
+    it "should create capability name methods" do
+      c1 = Class.new(Vagrant::GoPlugin::CapabilityPlugin::Capability)
+      c2 = Class.new(Vagrant::GoPlugin::CapabilityPlugin::Capability)
+      expect(Class).to receive(:new).and_return(c1)
+      expect(Class).to receive(:new).and_return(c2)
+      described_class.generate_host_capabilities(client, plugin_klass, plugin_type)
+      expect(c1).to respond_to(:stub_cap)
+      expect(c2).to respond_to(:other_cap)
+    end
+
+    it "should register host capability" do
+      expect(plugin_klass).to receive(:host_capability).with(:dummy, :stub_cap)
+      expect(plugin_klass).to receive(:host_capability).with(:dummy, :other_cap)
+      described_class.generate_host_capabilities(client, plugin_klass, plugin_type)
+    end
+
+    context "generated capability" do
+      let(:cap_class) { Class.new(Vagrant::GoPlugin::CapabilityPlugin::Capability) }
+      let(:response) { double(result: result) }
+      let(:result) { nil }
+
+      before {
+        expect(Class).to receive(:new).and_return(cap_class)
+        allow(Class).to receive(:new).and_call_original
+        described_class.generate_host_capabilities(client, plugin_klass, plugin_type)
+      }
+
+      it "should call guest_capability on the plugin client" do
+        expect(client).to receive(:host_capability).and_return(response)
+        cap_class.stub_cap(nil, nil)
+      end
+
+      context "when result is a hash" do
+        let(:result) { "{}" }
+
+        it "should convert hash to hash with indifferent access" do
+          expect(client).to receive(:host_capability).and_return(response)
+          expect(cap_class.stub_cap(nil, nil)).to be_a(Vagrant::Util::HashWithIndifferentAccess)
+        end
+      end
+    end
+  end
+
+  describe ".generate_provider_capabilities" do
+    let(:caps) {
+      [{provider: "dummy", name: "stub_cap"},
+        {provider: "dummy", name: "other_cap"}]}
+    let(:cap_response) {
+      Vagrant::Proto::ProviderCapabilityList.new(
+        capabilities: caps.map { |i|
+          Vagrant::Proto::ProviderCapability.new(i)})}
+    let(:plugin_klass) { double("plugin_klass") }
+    let(:plugin_type) { :testing }
+
+
+    before do
+      allow(client).to receive(:provider_capabilities).
+        and_return(cap_response)
+      allow(plugin_klass).to receive(:provider_capability)
+    end
+
+    it "should generate two new capability classes" do
+      expect(Class).to receive(:new).twice.
+        with(Vagrant::GoPlugin::CapabilityPlugin::Capability).
+        and_call_original
+      described_class.generate_provider_capabilities(client, plugin_klass, plugin_type)
+    end
+
+    it "should create capability name methods" do
+      c1 = Class.new(Vagrant::GoPlugin::CapabilityPlugin::Capability)
+      c2 = Class.new(Vagrant::GoPlugin::CapabilityPlugin::Capability)
+      expect(Class).to receive(:new).and_return(c1)
+      expect(Class).to receive(:new).and_return(c2)
+      described_class.generate_provider_capabilities(client, plugin_klass, plugin_type)
+      expect(c1).to respond_to(:stub_cap)
+      expect(c2).to respond_to(:other_cap)
+    end
+
+    it "should register provider capability" do
+      expect(plugin_klass).to receive(:provider_capability).with(:dummy, :stub_cap)
+      expect(plugin_klass).to receive(:provider_capability).with(:dummy, :other_cap)
+      described_class.generate_provider_capabilities(client, plugin_klass, plugin_type)
+    end
+
+    context "generated capability" do
+      let(:cap_class) { Class.new(Vagrant::GoPlugin::CapabilityPlugin::Capability) }
+      let(:response) { double(result: result) }
+      let(:result) { nil }
+
+      before {
+        expect(Class).to receive(:new).and_return(cap_class)
+        allow(Class).to receive(:new).and_call_original
+        described_class.generate_provider_capabilities(client, plugin_klass, plugin_type)
+      }
+
+      it "should call guest_capability on the plugin client" do
+        expect(client).to receive(:provider_capability).and_return(response)
+        cap_class.stub_cap(nil, nil)
+      end
+
+      context "when result is a hash" do
+        let(:result) { "{}" }
+
+        it "should convert hash to hash with indifferent access" do
+          expect(client).to receive(:provider_capability).and_return(response)
+          expect(cap_class.stub_cap(nil, nil)).to be_a(Vagrant::Util::HashWithIndifferentAccess)
+        end
+      end
+    end
+  end
+end

test/unit/vagrant/go_plugin/config_plugin_test.rb

@@ -0,0 +1,141 @@
+require_relative "../../base"
+
+describe Vagrant::GoPlugin::ConfigPlugin do
+  let(:client) { double("client") }
+
+  describe ".generate_config" do
+    let(:parent_name) { "test" }
+    let(:parent_klass) { double("parent_klass") }
+    let(:parent_type) { "dummy" }
+    let(:attributes_response) {
+      double("attributes_response",
+        items: attributes)
+    }
+    let(:attributes) { [] }
+
+    before do
+      allow(parent_klass).to receive(:config)
+      allow(client).to receive(:config_attributes).
+        and_return(attributes_response)
+    end
+
+    it "should register a new config class" do
+      expect(parent_klass).to receive(:config).
+        with(parent_name, parent_type) { |&block|
+        expect(block.call.ancestors).to include(Vagrant::GoPlugin::ConfigPlugin::Config)
+      }
+      described_class.generate_config(client, parent_name, parent_klass, parent_type)
+    end
+
+    it "should register the client within the class" do
+      expect(parent_klass).to receive(:config).
+        with(parent_name, parent_type) { |&block|
+        expect(block.call.plugin_client).to eq(client)
+      }
+      described_class.generate_config(client, parent_name, parent_klass, parent_type)
+    end
+
+    context "when attributes are provided" do
+      let(:attributes) { ["a_one", "a_two"] }
+
+      it "should add accessor instance methods to the class" do
+        expect(parent_klass).to receive(:config).
+          with(parent_name, parent_type) { |&block|
+          expect(block.call.instance_methods).to include(:a_one)
+          expect(block.call.instance_methods).to include(:a_two)
+        }
+        described_class.generate_config(client, parent_name, parent_klass, parent_type)
+      end
+    end
+  end
+
+  describe Vagrant::GoPlugin::ConfigPlugin::Config do
+    let(:machine) { double("machine") }
+    let(:subject) {
+      c = Class.new(described_class)
+      c.plugin_client = client
+      c.new
+    }
+
+    describe "#validate" do
+      let(:response) { double("response", items: errors) }
+      let(:errors) { ["errors"] }
+
+      before do
+        allow(machine).to receive(:to_json).and_return("{}")
+        allow(client).to receive(:config_validate).and_return(response)
+      end
+
+      it "should call client to validate" do
+        expect(client).to receive(:config_validate).
+          with(instance_of(Vagrant::Proto::Configuration)).
+          and_return(response)
+        subject.validate(machine)
+      end
+
+      it "should return list of validation errors" do
+        expect(subject.validate(machine)).to eq(errors)
+      end
+    end
+
+    describe "#finalize!" do
+      let(:response) { double("response", data: result) }
+      let(:result) { "null" }
+
+      before do
+        allow(client).to receive(:config_finalize).and_return(response)
+      end
+
+      it "should return the config instance" do
+        expect(subject.finalize!).to eq(subject)
+      end
+
+      it "should call client to finalize" do
+        expect(client).to receive(:config_finalize).
+          with(instance_of(Vagrant::Proto::Configuration)).
+          and_return(response)
+        subject.finalize!
+      end
+
+      context "when configuration data is returned" do
+        let(:result) {
+          {attr1: true, attr2: "value"}.to_json
+        }
+
+        it "should create accessor methods to configuration data" do
+          subject.finalize!
+          expect(subject).to respond_to(:attr1)
+          expect(subject).to respond_to(:attr2)
+        end
+
+        it "should return data from reader methods" do
+          subject.finalize!
+          expect(subject.attr1).to eq(true)
+          expect(subject.attr2).to eq("value")
+        end
+      end
+
+      describe "#local_data" do
+        it "should return an empty hash" do
+          expect(subject.local_data).to be_empty
+        end
+
+        context "with config attributes set" do
+          let(:response) { double("response", data: result) }
+          let(:result) { {attr1: true, attr2: "value"}.to_json }
+
+          before do
+            allow(client).to receive(:config_finalize).and_return(response)
+            subject.finalize!
+          end
+
+          it "should return data values" do
+            result = subject.local_data
+            expect(result[:attr1]).to eq(true)
+            expect(result[:attr2]).to eq("value")
+          end
+        end
+      end
+    end
+  end
+end

test/unit/vagrant/go_plugin/core_test.rb

@@ -0,0 +1,41 @@
+require_relative "../../base"
+
+describe Vagrant::GoPlugin::GRPCPlugin do
+  let(:client) { double("client") }
+  let(:subject) { Class.new.tap { |c| c.include(described_class) } }
+
+  describe ".plugin_client=" do
+    it "should set the plugin client" do
+      expect(subject.plugin_client = client).to eq(client)
+      expect(subject.plugin_client).to eq(client)
+    end
+
+    it "should error if plugin is already set" do
+      subject.plugin_client = client
+      expect { subject.plugin_client = client }.
+        to raise_error(ArgumentError)
+    end
+  end
+
+  describe ".plugin_client" do
+    it "should return nil when client has not been set" do
+      expect(subject.plugin_client).to be_nil
+    end
+
+    it "should return client when it has been set" do
+      subject.plugin_client = client
+      expect(subject.plugin_client).to eq(client)
+    end
+  end
+
+  describe "#plugin_client" do
+    it "should be nil when client has not been set" do
+      expect(subject.new.plugin_client).to be_nil
+    end
+
+    it "should return client when client has been set" do
+      subject.plugin_client = client
+      expect(subject.new.plugin_client).to eq(client)
+    end
+  end
+end

test/unit/vagrant/go_plugin/interface_test.rb

@@ -0,0 +1,56 @@
+require_relative "../../base"
+
+describe Vagrant::GoPlugin::Interface do
+  before do
+    allow_any_instance_of(described_class).to receive(:_setup)
+  end
+
+  describe "#load_plugins" do
+    let(:path) { double("path", to_s: "path") }
+
+    it "should raise error if path is not a directory" do
+      expect(File).to receive(:directory?).with(path.to_s).and_return(false)
+      expect { subject.load_plugins(path) }.to raise_error(ArgumentError)
+    end
+
+    it "should load plugins if path is a directory" do
+      expect(File).to receive(:directory?).with(path.to_s).and_return(true)
+      expect(subject).to receive(:_load_plugins).with(path.to_s)
+      subject.load_plugins(path)
+    end
+  end
+
+  describe "#register_plugins" do
+    it "should load Provider and SyncedFolder plugins" do
+      expect(subject).to receive(:load_providers)
+      expect(subject).to receive(:load_synced_folders)
+      subject.register_plugins
+    end
+  end
+
+  describe "#setup" do
+    after { subject }
+
+    it "should register at_exit action" do
+      expect(Kernel).to receive(:at_exit)
+      subject
+    end
+
+    it "should run the setup action" do
+      expect_any_instance_of(described_class).to receive(:_setup)
+    end
+
+    it "should only run the setup process once" do
+      expect_any_instance_of(described_class).to receive(:_setup).once
+      expect(subject.logger).to receive(:warn)
+      subject.setup
+    end
+  end
+
+  describe "#teardown" do
+    it "should run the teardown action" do
+      expect(subject).to receive(:_teardown)
+      subject.teardown
+    end
+  end
+end

test/unit/vagrant/go_plugin/manager_test.rb

@@ -0,0 +1,148 @@
+require_relative "../../base"
+
+describe Vagrant::GoPlugin::Manager do
+  include_context "unit"
+
+  let(:env) do
+    test_env.vagrantfile("")
+    test_env.create_vagrant_env
+  end
+
+  before do
+    allow(FileUtils).to receive(:mkdir_p)
+  end
+
+  describe ".instance" do
+    it "should return instance of manager" do
+      expect(described_class.instance).to be_a(described_class)
+    end
+
+    it "should cache instance" do
+      expect(described_class.instance).to be(described_class.instance)
+    end
+  end
+
+  describe ".new" do
+    it "should create the installation directory" do
+      expect(FileUtils).to receive(:mkdir_p).with(Vagrant::GoPlugin::INSTALL_DIRECTORY)
+      subject
+    end
+
+    it "should create installation temporary directory" do
+      expect(FileUtils).to receive(:mkdir_p).with(/tmp$/)
+      subject
+    end
+
+    it "should generate user state file" do
+      expect(subject.user_file).to be_a(Vagrant::Plugin::StateFile)
+    end
+  end
+
+  describe "#globalize!" do
+    let(:entries) { [double("entry1"), double("entry2")] }
+
+    before do
+      allow(File).to receive(:directory?).and_return(false)
+      allow(Dir).to receive(:glob).and_return(entries)
+      allow(Vagrant::GoPlugin).to receive_message_chain(:interface, :register_plugins)
+    end
+
+    context "when entries are not directories" do
+      before { allow(File).to receive(:directory?).and_return(false) }
+
+      it "should not load any plugins" do
+        interface = double("interface", register_plugins: nil)
+        allow(Vagrant::GoPlugin).to receive(:interface).and_return(interface)
+        expect(interface).not_to receive(:load_plugins)
+        subject.globalize!
+      end
+    end
+
+    context "when entries are directories" do
+      before { allow(File).to receive(:directory?).and_return(true) }
+
+      it "should load all entries" do
+        expect(Vagrant::GoPlugin).to receive_message_chain(:interface, :load_plugins).with(entries.first)
+        expect(Vagrant::GoPlugin).to receive_message_chain(:interface, :load_plugins).with(entries.last)
+        subject.globalize!
+      end
+    end
+
+    it "should register plugins after loading" do
+      expect(Vagrant::GoPlugin).to receive_message_chain(:interface, :register_plugins)
+      subject.globalize!
+    end
+  end
+
+  describe "#localize!" do
+  end
+
+  describe "#install_plugin" do
+    let(:plugin_name) { "test_plugin_name" }
+    let(:remote_source) { double("remote_source") }
+    let(:downloader) { double("downloader", download!: nil) }
+
+    before do
+      allow(FileUtils).to receive(:mkdir_p)
+      allow(Dir).to receive(:mktmpdir)
+      allow(Vagrant::Util::Downloader).to receive(:new).and_return(downloader)
+      allow(Zip::File).to receive(:open)
+    end
+
+    after { subject.install_plugin(plugin_name, remote_source) }
+
+    it "should create plugin directory for plugin name" do
+      expect(FileUtils).to receive(:mkdir_p).with(/test_plugin_name$/)
+    end
+
+    it "should create a temporary directory to download and unpack" do
+      expect(Dir).to receive(:mktmpdir).with(/go-plugin/, any_args)
+    end
+
+    it "should download the remote file" do
+      expect(Dir).to receive(:mktmpdir).with(any_args).and_yield("tmpdir")
+      expect(downloader).to receive(:download!)
+    end
+
+    it "should unzip the downloaded file" do
+      expect(Dir).to receive(:mktmpdir).with(any_args).and_yield("tmpdir")
+      expect(Zip::File).to receive(:open).with(/plugin.zip/)
+    end
+
+    it "should add the plugin to the user file" do
+      expect(subject.user_file).to receive(:add_go_plugin).and_call_original
+      expect(subject.user_file.has_go_plugin?("test_plugin_name")).to be_truthy
+    end
+  end
+
+  describe "#uninstall_plugin" do
+    let(:plugin_name) { "test_plugin_name" }
+
+    before do
+      allow(File).to receive(:directory?).and_call_original
+      allow(FileUtils).to receive(:rm_rf)
+    end
+
+    after { subject.uninstall_plugin(plugin_name) }
+
+    it "should remove plugin path when installed" do
+      expect(File).to receive(:directory?).with(/test_plugin_name/).and_return(true)
+      expect(FileUtils).to receive(:rm_rf).with(/test_plugin_name/)
+    end
+
+    it "should not remove plugin path when not installed" do
+      expect(File).to receive(:directory?).with(/test_plugin_name/).and_return(false)
+      expect(FileUtils).not_to receive(:rm_rf).with(/test_plugin_name/)
+    end
+
+    it "should have plugin name removed from user file when installed" do
+      expect(File).to receive(:directory?).with(/test_plugin_name/).and_return(true)
+      expect(subject.user_file).to receive(:remove_go_plugin).with(plugin_name)
+    end
+
+    it "should have plugin name removed from user file when not installed" do
+      expect(File).to receive(:directory?).with(/test_plugin_name/).and_return(false)
+      expect(subject.user_file).to receive(:remove_go_plugin).with(plugin_name)
+    end
+  end
+end

test/unit/vagrant/go_plugin/provider_plugin_test.rb

@@ -0,0 +1,273 @@
+require_relative "../../base"
+
+describe Vagrant::GoPlugin::ProviderPlugin do
+  let(:client) { double("client") }
+
+  describe Vagrant::GoPlugin::ProviderPlugin::Action do
+    let(:described_class) { Class.new(Vagrant::GoPlugin::ProviderPlugin::Action) }
+
+    it "should be a GRPCPlugin" do
+      expect(described_class.ancestors).to include(Vagrant::GoPlugin::GRPCPlugin)
+    end
+
+    describe ".action_name" do
+      it "should return nil when unset" do
+        expect(described_class.action_name).to be_nil
+      end
+
+      it "should return defined action name when set" do
+        described_class.action_name = "test_action"
+        expect(described_class.action_name).to eq("test_action")
+      end
+    end
+
+    describe ".action_name=" do
+      it "should convert action name to string" do
+        described_class.action_name = :test_action
+        expect(described_class.action_name).to be_a(String)
+      end
+
+      it "should set the action name" do
+        described_class.action_name = "test_action"
+        expect(described_class.action_name).to eq("test_action")
+      end
+
+      it "should error if action name is already set" do
+        described_class.action_name = "test_action"
+        expect { described_class.action_name = "test_action" }.
+          to raise_error(ArgumentError)
+      end
+
+      it "should freeze action name" do
+        described_class.action_name = "test_action"
+        expect(described_class.action_name).to be_frozen
+      end
+    end
+
+    describe "#call" do
+      let(:app) { double("app") }
+      let(:env) { {"key1" => "value1", "key2" => "value2"} }
+      let(:response_env) {
+        {"key1" => "value1", "key2" => "value2"}
+      }
+      let(:response) { double("response", result: response_env.to_json) }
+
+      let(:subject) {
+        described_class.plugin_client = client
+        described_class.new(app, {})
+      }
+
+      before do
+        described_class.action_name = "test_action"
+        allow(app).to receive(:call)
+        allow(client).to receive(:run_action).and_return(response)
+      end
+
+      it "should call the next item in the middleware" do
+        expect(app).to receive(:call)
+        subject.call(env)
+      end
+
+      it "should call the client" do
+        expect(client).to receive(:run_action).and_return(response)
+        subject.call(env)
+      end
+
+      context "when new data is provided in result" do
+        let(:response_env) { {"new_data" => "value"} }
+
+        it "should include new data when calling next action" do
+          expect(app).to receive(:call).
+            with(hash_including("new_data" => "value", "key1" => "value1"))
+          subject.call(env)
+        end
+      end
+    end
+  end
+
+  describe Vagrant::GoPlugin::ProviderPlugin::Provider do
+    let(:described_class) {
+      Class.new(Vagrant::GoPlugin::ProviderPlugin::Provider).tap { |c|
+        c.plugin_client = client
+      }
+    }
+    let(:machine) { double("machine") }
+    let(:subject) { described_class.new(machine) }
+
+    it "should be a GRPCPlugin" do
+      expect(described_class.ancestors).to include(Vagrant::GoPlugin::GRPCPlugin)
+    end
+
+    describe "#name" do
+      let(:name) { double("name") }
+      let(:response) { double("response", name: name) }
+
+      before { allow(client).to receive(:name).and_return(response) }
+
+      it "should request name from the client" do
+        expect(client).to receive(:name).and_return(response)
+        subject.name
+      end
+
+      it "should return the plugin name" do
+        expect(subject.name).to eq(name)
+      end
+
+      it "should only call the client once" do
+        expect(client).to receive(:name).once.and_return(response)
+        subject.name
+      end
+    end
+
+    describe "#action" do
+      let(:action_name) { "test_action" }
+      let(:response) { double("response", items: actions) }
+      let(:actions) { ["self::TestAction"] }
+
+      before do
+        allow(client).to receive(:action).and_return(response)
+      end
+
+      it "should return a builder instance" do
+        expect(subject.action(action_name)).to be_a(Vagrant::Action::Builder)
+      end
+
+      it "should call the plugin client" do
+        expect(client).to receive(:action).
+          with(instance_of(Vagrant::Proto::GenericAction)).
+          and_return(response)
+        subject.action(action_name)
+      end
+
+      it "should create a new custom action class" do
+        builder = subject.action(action_name)
+        action = builder.stack.first.first
+        expect(action.ancestors).to include(Vagrant::GoPlugin::ProviderPlugin::Action)
+        expect(action.action_name).to eq("TestAction")
+      end
+
+      context "when given non-local action name" do
+        let(:actions) { ["Vagrant::Action::Builtin::Call"] }
+
+        it "should load the existing action class" do
+          builder = subject.action(action_name)
+          action = builder.stack.first.first
+          expect(action).to eq(Vagrant::Action::Builtin::Call)
+        end
+      end
+    end
+
+    describe "#capability" do
+      let(:cap_name) { "test_cap" }
+      let(:response) { double("response", result: result.to_json) }
+      let(:result) { nil }
+
+      before do
+        allow(subject).to receive(:name).and_return("dummy_provider")
+        allow(client).to receive(:provider_capability).and_return(response)
+      end
+
+      it "should call the plugin client" do
+        expect(client).to receive(:provider_capability).
+          with(instance_of(Vagrant::Proto::ProviderCapabilityRequest))
+          .and_return(response)
+        subject.capability(cap_name)
+      end
+
+      it "should deserialize result" do
+        expect(subject.capability(cap_name)).to eq(result)
+      end
+
+      context "when hash value is returned" do
+        let(:result) { {key: "value"} }
+
+        it "should return indifferent access hash" do
+          r = subject.capability(cap_name)
+          expect(r[:key]).to eq(result[:key])
+          expect(r).to be_a(Vagrant::Util::HashWithIndifferentAccess)
+        end
+      end
+
+      context "when arguments are provided" do
+        let(:args) { ["arg1", {"key" => "value"}] }
+
+        it "should serialize arguments when sent to plugin client" do
+          expect(client).to receive(:provider_capability) do |req|
+            expect(req.arguments).to eq(args.to_json)
+            response
+          end
+          subject.capability(cap_name, *args)
+        end
+      end
+    end
+
+    describe "#is_installed?" do
+      it "should call plugin client" do
+        expect(client).to receive(:is_installed).and_return(double("response", result: true))
+        expect(subject.is_installed?).to eq(true)
+      end
+    end
+
+    describe "#is_usable?" do
+      it "should call plugin client" do
+        expect(client).to receive(:is_usable).and_return(double("response", result: true))
+        expect(subject.is_usable?).to eq(true)
+      end
+    end
+
+    describe "#machine_id_changed" do
+      it "should call plugin client" do
+        expect(client).to receive(:machine_id_changed).and_return(double("response", result: true))
+        expect(subject.machine_id_changed).to be_nil
+      end
+    end
+
+    describe "#ssh_info" do
+      let(:response) {
+        Vagrant::Proto::MachineSshInfo.new(
+          host: "localhost",
+          port: 2222,
+          private_key_path: "/key/path",
+          username: "vagrant"
+        )
+      }
+
+      before { allow(client).to receive(:ssh_info).and_return(response) }
+
+      it "should return hash with indifferent access result" do
+        expect(subject.ssh_info).to be_a(Vagrant::Util::HashWithIndifferentAccess)
+      end
+
+      it "should include ssh information" do
+        result = subject.ssh_info
+        expect(result[:host]).to eq(response.host)
+        expect(result[:port]).to eq(response.port)
+        expect(result[:private_key_path]).to eq(response.private_key_path)
+        expect(result[:username]).to eq(response.username)
+      end
+    end
+
+    describe "#state" do
+      let(:response) {
+        Vagrant::Proto::MachineState.new(
+          id: "machine-id",
+          short_description: "running",
+          long_description: "it's really running"
+        )
+      }
+
+      before { allow(client).to receive(:state).and_return(response) }
+
+      it "should return a MachineState instance" do
+        expect(subject.state).to be_a(Vagrant::MachineState)
+      end
+
+      it "should set the state attributes" do
+        result = subject.state
+        expect(result.id).to eq(response.id)
+        expect(result.short_description).to eq(response.short_description)
+        expect(result.long_description).to eq(response.long_description)
+      end
+    end
+  end
+end

test/unit/vagrant/go_plugin/synced_folder_plugin_test.rb

@@ -0,0 +1,73 @@
+require_relative "../../base"
+
+describe Vagrant::GoPlugin::SyncedFolderPlugin::SyncedFolder do
+  let(:subject) {
+    Class.new(described_class).tap { |c|
+      c.plugin_client = client } }
+  let(:client) { double("client") }
+  let(:machine) { double("machine", to_json: "{}") }
+  let(:folders) { double("folders", to_json: "{}") }
+  let(:options) { double("options", to_json: "{}") }
+
+  it "should be a GRPCPlugin" do
+    expect(subject).to be_a(Vagrant::GoPlugin::GRPCPlugin)
+  end
+
+  describe "#cleanup" do
+    it "should call plugin client" do
+      expect(client).to receive(:cleanup).
+        with(instance_of(Vagrant::Proto::SyncedFolders))
+      subject.cleanup(machine, options)
+    end
+  end
+
+  describe "#disable" do
+    it "should call plugin client" do
+      expect(client).to receive(:disable).
+        with(instance_of(Vagrant::Proto::SyncedFolders))
+      subject.disable(machine, folders, options)
+    end
+  end
+
+  describe "#enable" do
+    it "should call plugin client" do
+      expect(client).to receive(:enable).
+        with(instance_of(Vagrant::Proto::SyncedFolders))
+      subject.enable(machine, folders, options)
+    end
+  end
+
+  describe "#prepare" do
+    it "should call plugin client" do
+      expect(client).to receive(:prepare).
+        with(instance_of(Vagrant::Proto::SyncedFolders))
+      subject.prepare(machine, folders, options)
+    end
+  end
+
+  describe "#usable?" do
+    let(:response) { Vagrant::Proto::Valid.new(result: true) }
+
+    it "should call the plugin client" do
+      expect(client).to receive(:is_usable).
+        with(instance_of(Vagrant::Proto::Machine)).
+        and_return(response)
+      expect(subject.usable?).to eq(true)
+    end
+  end
+
+  describe "#name" do
+    let(:response) { Vagrnat::Proto::Identifier.new(name: "dummy") }
+
+    it "should call the plugin client" do
+      expect(client).to receive(:name).and_return(response)
+      expect(subject.name).to eq(response.name)
+    end
+
+    it "should only call the plugin client once" do
+      expect(client).to receive(:name).once.and_return(response)
+      expect(subject.name).to eq(response.name)
+      expect(subject.name).to eq(response.name)
+    end
+  end
+end

test/unit/vagrant/go_plugin_test.rb

@@ -0,0 +1,29 @@
+require_relative "../base"
+
+describe Vagrant::GoPlugin do
+  describe "INSTALL_DIRECTORY constant" do
+    let(:subject) { described_class.const_get(:INSTALL_DIRECTORY) }
+
+    it "should be a String" do
+      expect(subject).to be_a(String)
+    end
+
+    it "should be frozen" do
+      expect(subject).to be_frozen
+    end
+
+    it "should be within the user data path" do
+      expect(subject).to start_with(Vagrant.user_data_path.to_s)
+    end
+  end
+
+  describe ".interface" do
+    it "should return an interface instance" do
+      expect(described_class.interface).to be_a(Vagrant::GoPlugin::Interface)
+    end
+
+    it "should cache the interface instance" do
+      expect(described_class.interface).to be(described_class.interface)
+    end
+  end
+end

test/unit/vagrant/plugin/state_file_test.rb

@@ -118,4 +118,56 @@ describe Vagrant::Plugin::StateFile do
         to raise_error(Vagrant::Errors::PluginStateFileParseError)
     end
   end
+
+  context "go plugin usage" do
+    describe "#add_go_plugin" do
+      it "should add plugin to list of installed go plugins" do
+        subject.add_go_plugin("foo", source: "http://localhost/foo.zip")
+        expect(subject.installed_go_plugins).to include("foo")
+      end
+
+      it "should update source when added again" do
+        subject.add_go_plugin("foo", source: "http://localhost/foo.zip")
+        expect(subject.installed_go_plugins["foo"]["source"]).to eq("http://localhost/foo.zip")
+        subject.add_go_plugin("foo", source: "http://localhost/foo1.zip")
+        expect(subject.installed_go_plugins["foo"]["source"]).to eq("http://localhost/foo1.zip")
+      end
+    end
+
+    describe "#remove_go_plugin" do
+      before do
+        subject.add_go_plugin("foo", source: "http://localhost/foo.zip")
+      end
+
+      it "should remove the installed plugin" do
+        subject.remove_go_plugin("foo")
+        expect(subject.installed_go_plugins).not_to include("foo")
+      end
+
+      it "should remove plugin not installed" do
+        subject.remove_go_plugin("foo")
+        expect(subject.installed_go_plugins).not_to include("foo")
+        subject.remove_go_plugin("foo")
+        expect(subject.installed_go_plugins).not_to include("foo")
+      end
+    end
+
+    describe "#has_go_plugin?" do
+      before do
+        subject.add_go_plugin("foo", source: "http://localhost/foo.zip")
+      end
+
+      it "should return true when plugin is installed" do
+        expect(subject.has_go_plugin?("foo")).to be_truthy
+      end
+
+      it "should return false when plugin is not installed" do
+        expect(subject.has_go_plugin?("fee")).to be_falsey
+      end
+
+      it "should allow symbol names" do
+        expect(subject.has_go_plugin?(:foo)).to be_truthy
+      end
+    end
+  end
 end

vagrant.gemspec

@@ -13,6 +13,7 @@ Gem::Specification.new do |s|
   s.description   = "Vagrant is a tool for building and distributing virtualized development environments."
 
   s.required_ruby_version     = "~> 2.2", "< 2.7"
+
   s.required_rubygems_version = ">= 1.3.6"
   s.rubyforge_project         = "vagrant"
 
@@ -22,6 +23,8 @@ Gem::Specification.new do |s|
   s.add_dependency "erubis", "~> 2.7.0"
   s.add_dependency "i18n", "~> 1.1.1"
   s.add_dependency "listen", "~> 3.1.5"
+  s.add_dependency "grpc", "~> 1.19.0"
+  s.add_dependency "grpc-tools", "~> 1.19.0"
   s.add_dependency "hashicorp-checkpoint", "~> 0.1.5"
   s.add_dependency "log4r", "~> 1.1.9", "< 1.1.11"
   s.add_dependency "net-ssh", "~> 5.1.0"
@@ -49,6 +52,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency "rspec-its", "~> 1.2.0"
   s.add_development_dependency "webmock", "~> 2.3.1"
   s.add_development_dependency "fake_ftp", "~> 0.1.1"
+  s.add_development_dependency "rake-compiler"
 
   # The following block of code determines the files that should be included
   # in the gem. It does this by reading all the files in the directory where

website/source/docs/experimental/index.html.md

@@ -54,3 +54,7 @@ Enabling this feature allows all provisioners to specify `before` and `after`
 options. These options allow provisioners to be configured to run before or after
 any given "root" provisioner. more information about these options can be found
 on the [base provisioner documentation page](/docs/provisioning/basic_usage.html)
+
+### `go_plugin`
+
+Enabling this feature turns on support for [go-plugin](https://github.com/hashicorp/go-plugin) based plugin for Vagrant.