From 69d9bc0fe85e65ec21ff6ee8d19b9b77da1ef7e9 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Thu, 5 Nov 2015 11:50:10 -0800
Subject: [PATCH 1/3] Environment can_install_provider and install_provider

---
 lib/vagrant/environment.rb                   | 26 ++++++++++++
 lib/vagrant/plugin/v2/provider.rb            | 15 +++++++
 test/unit/vagrant/environment_test.rb        | 42 ++++++++++++++++++++
 test/unit/vagrant/plugin/v2/provider_test.rb |  4 ++
 4 files changed, 87 insertions(+)

diff --git a/lib/vagrant/environment.rb b/lib/vagrant/environment.rb
index 015e4b95f..034d71163 100644
--- a/lib/vagrant/environment.rb
+++ b/lib/vagrant/environment.rb
@@ -383,6 +383,26 @@ module Vagrant
       raise Errors::NoDefaultProvider
     end
 
+    # Returns whether or not we know how to install the provider with
+    # the given name.
+    #
+    # @return [Boolean]
+    def can_install_provider?(name)
+      host.capability?(provider_install_key(name))
+    end
+
+    # Installs the provider with the given name.
+    #
+    # This will raise an exception if we don't know how to install the
+    # provider with the given name. You should guard this call with
+    # `can_install_provider?` for added safety.
+    #
+    # An exception will be raised if there are any failures installing
+    # the provider.
+    def install_provider(name)
+      host.capability(provider_install_key(name))
+    end
+
     # Returns the collection of boxes for the environment.
     #
     # @return [BoxCollection]
@@ -883,6 +903,12 @@ module Vagrant
       nil
     end
 
+    # Returns the key used for the host capability for provider installs
+    # of the given name.
+    def provider_install_key(name)
+      "provider_install_#{name}".to_sym
+    end
+
     # This upgrades a home directory that was in the v1.1 format to the
     # v1.5 format. It will raise exceptions if anything fails.
     def upgrade_home_path_v1_1
diff --git a/lib/vagrant/plugin/v2/provider.rb b/lib/vagrant/plugin/v2/provider.rb
index 0ea7a1f13..3e96d86e1 100644
--- a/lib/vagrant/plugin/v2/provider.rb
+++ b/lib/vagrant/plugin/v2/provider.rb
@@ -24,6 +24,21 @@ module Vagrant
           true
         end
 
+        # This is called early, before a machine is instantiated, to check
+        # if this provider is installed. This should return true or false.
+        #
+        # If the provider is not installed and Vagrant determines it is
+        # able to install this provider, then it will do so. Installation
+        # is done by calling Environment.install_provider.
+        #
+        # If Environment.can_install_provider? returns false, then an error
+        # will be shown to the user.
+        def self.installed?
+          # By default return true for backwards compat so all providers
+          # continue to work.
+          true
+        end
+
         # Initialize the provider to represent the given machine.
         #
         # @param [Vagrant::Machine] machine The machine that this provider
diff --git a/test/unit/vagrant/environment_test.rb b/test/unit/vagrant/environment_test.rb
index c5cf8370d..6a595fb57 100644
--- a/test/unit/vagrant/environment_test.rb
+++ b/test/unit/vagrant/environment_test.rb
@@ -25,6 +25,48 @@ describe Vagrant::Environment do
   let(:instance)  { env.create_vagrant_env }
   subject { instance }
 
+  describe "#can_install_provider?" do
+    let(:plugin_hosts) { {} }
+    let(:plugin_host_caps) { {} }
+
+    before do
+      m = Vagrant.plugin("2").manager
+      m.stub(hosts: plugin_hosts)
+      m.stub(host_capabilities: plugin_host_caps)
+
+      # Detect the host
+      env.vagrantfile <<-VF
+      Vagrant.configure("2") do |config|
+        config.vagrant.host = nil
+      end
+      VF
+
+      # Setup the foo host by default
+      plugin_hosts[:foo] = [detect_class(true), nil]
+    end
+
+    it "should return whether it can install or not" do
+      plugin_host_caps[:foo] = { provider_install_foo: Class }
+
+      expect(subject.can_install_provider?(:foo)).to be_true
+      expect(subject.can_install_provider?(:bar)).to be_false
+    end
+  end
+
+  describe "#install_provider" do
+    let(:host) { double(:host) }
+
+    before do
+      allow(subject).to receive(:host).and_return(host)
+    end
+
+    it "should install the correct provider" do
+      expect(host).to receive(:capability).with(:provider_install_foo)
+
+      subject.install_provider(:foo)
+    end
+  end
+
   describe "#home_path" do
     it "is set to the home path given" do
       Dir.mktmpdir do |dir|
diff --git a/test/unit/vagrant/plugin/v2/provider_test.rb b/test/unit/vagrant/plugin/v2/provider_test.rb
index c27274db1..634b311c6 100644
--- a/test/unit/vagrant/plugin/v2/provider_test.rb
+++ b/test/unit/vagrant/plugin/v2/provider_test.rb
@@ -12,6 +12,10 @@ describe Vagrant::Plugin::V2::Provider do
     expect(described_class).to be_usable
   end
 
+  it "should be installed by default" do
+    expect(described_class).to be_installed
+  end
+
   it "should return nil by default for actions" do
     expect(instance.action(:whatever)).to be_nil
   end

From baea923e9cf3327336ad896f5024541339e3b599 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Thu, 5 Nov 2015 13:58:15 -0800
Subject: [PATCH 2/3] commands/up: automatically install providers

---
 lib/vagrant/environment.rb               |  2 +
 plugins/commands/up/command.rb           | 85 +++++++++++++++++++-----
 plugins/providers/virtualbox/provider.rb |  9 +++
 templates/locales/en.yml                 |  7 ++
 4 files changed, 87 insertions(+), 16 deletions(-)

diff --git a/lib/vagrant/environment.rb b/lib/vagrant/environment.rb
index 034d71163..88779a2e9 100644
--- a/lib/vagrant/environment.rb
+++ b/lib/vagrant/environment.rb
@@ -309,6 +309,7 @@ module Vagrant
     def default_provider(**opts)
       opts[:exclude]       = Set.new(opts[:exclude]) if opts[:exclude]
       opts[:force_default] = true if !opts.key?(:force_default)
+      opts[:check_usable] = true if !opts.key?(:check_usable)
 
       default = ENV["VAGRANT_DEFAULT_PROVIDER"]
       default = nil if default == ""
@@ -376,6 +377,7 @@ module Vagrant
 
       # Find the matching implementation
       ordered.each do |_, key, impl, _|
+        return key if !opts[:check_usable]
         return key if impl.usable?(false)
       end
 
diff --git a/plugins/commands/up/command.rb b/plugins/commands/up/command.rb
index 826bea0ae..b93e859cf 100644
--- a/plugins/commands/up/command.rb
+++ b/plugins/commands/up/command.rb
@@ -1,4 +1,5 @@
 require 'optparse'
+require 'set'
 
 require "vagrant"
 
@@ -16,6 +17,7 @@ module VagrantPlugins
       def execute
         options = {}
         options[:destroy_on_error] = true
+        options[:install_provider] = true
         options[:parallel] = true
         options[:provision_ignore_sentinel] = false
 
@@ -41,6 +43,11 @@ module VagrantPlugins
                "Back the machine with a specific provider") do |provider|
             options[:provider] = provider
           end
+
+          o.on("--[no-]install-provider",
+               "If possible, install the provider if it isn't installed") do |p|
+            options[:install_provider] = p
+          end
         end
 
         # Parse the options
@@ -53,24 +60,32 @@ module VagrantPlugins
         # Go over each VM and bring it up
         @logger.debug("'Up' each target VM...")
 
-        # Build up the batch job of what we'll do
-        machines = []
-        @env.batch(options[:parallel]) do |batch|
-          names = argv
-          if names.empty?
-            autostart = false
-            @env.vagrantfile.machine_names_and_options.each do |n, o|
-              autostart = true if o.key?(:autostart)
-              o[:autostart] = true if !o.key?(:autostart)
-              names << n.to_s if o[:autostart]
-            end
-
-            # If we have an autostart key but no names, it means that
-            # all machines are autostart: false and we don't start anything.
-            names = nil if autostart && names.empty?
+        # Get the names of the machines we want to bring up
+        names = argv
+        if names.empty?
+          autostart = false
+          @env.vagrantfile.machine_names_and_options.each do |n, o|
+            autostart = true if o.key?(:autostart)
+            o[:autostart] = true if !o.key?(:autostart)
+            names << n.to_s if o[:autostart]
           end
 
-          if names
+          # If we have an autostart key but no names, it means that
+          # all machines are autostart: false and we don't start anything.
+          names = nil if autostart && names.empty?
+        end
+
+        # Build up the batch job of what we'll do
+        machines = []
+        if names
+          # If we're installing providers, then do that. We don't
+          # parallelize this step because it is likely the same provider
+          # anyways.
+          if options[:install_provider]
+            install_providers(names)
+          end
+
+          @env.batch(options[:parallel]) do |batch|
             with_target_vms(names, provider: options[:provider]) do |machine|
               @env.ui.info(I18n.t(
                 "vagrant.commands.up.upping",
@@ -106,6 +121,44 @@ module VagrantPlugins
         # Success, exit status 0
         0
       end
+
+      protected
+
+      def install_providers(names)
+        # First create a set of all the providers we need to check for.
+        # Most likely this will be a set of one.
+        providers = Set.new
+        names.each do |name|
+          providers.add(@env.default_provider(machine: name.to_sym, check_usable: false))
+        end
+
+        # Go through and determine if we can install the providers
+        providers.delete_if do |name|
+          !@env.can_install_provider?(name)
+        end
+
+        # Install the providers if we have to
+        providers.each do |name|
+          # Find the provider. Ignore if we can't find it, this error
+          # will pop up later in the process.
+          parts = Vagrant.plugin("2").manager.providers[name]
+          next if !parts
+
+          # If the provider is already installed, then our work here is done
+          cls = parts[0]
+          next if cls.installed?
+
+          # Some human-friendly output
+          ui = Vagrant::UI::Prefixed.new(@env.ui, "")
+          ui.output(I18n.t(
+            "vagrant.installing_provider",
+            provider: name.to_s))
+          ui.detail(I18n.t("vagrant.installing_provider_detail"))
+
+          # Install the provider
+          @env.install_provider(name)
+        end
+      end
     end
   end
 end
diff --git a/plugins/providers/virtualbox/provider.rb b/plugins/providers/virtualbox/provider.rb
index 969fb4718..6bde344d2 100644
--- a/plugins/providers/virtualbox/provider.rb
+++ b/plugins/providers/virtualbox/provider.rb
@@ -5,6 +5,15 @@ module VagrantPlugins
     class Provider < Vagrant.plugin("2", :provider)
       attr_reader :driver
 
+      def self.installed?
+        Driver::Meta.new
+        true
+      rescue Vagrant::Errors::VirtualBoxInvalidVersion
+        return false
+      rescue Vagrant::Errors::VirtualBoxNotDetected
+        return false
+      end
+
       def self.usable?(raise_error=false)
         # Instantiate the driver, which will determine the VirtualBox
         # version and all that, which checks for VirtualBox being present
diff --git a/templates/locales/en.yml b/templates/locales/en.yml
index 2bafd0f55..3b7094310 100644
--- a/templates/locales/en.yml
+++ b/templates/locales/en.yml
@@ -154,6 +154,13 @@ en:
       Inserting generated public key within guest...
     inserting_remove_key: |-
       Removing insecure key from the guest if it's present...
+    installing_provider: |-
+      Provider '%{provider}' not found. We'll automatically install it now...
+    installing_provider_detail: |-
+      The installation process will start below. Human interaction may be
+      required at some points. If you're uncomfortable with automatically
+      installing this provider, you can safely Ctrl-C this process and install
+      it manually.
     list_commands: |-
       Below is a listing of all available Vagrant commands and a brief
       description of what they do.

From c017340f699a199a7043817788cb9f7abecac37f Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Thu, 5 Nov 2015 13:59:08 -0800
Subject: [PATCH 3/3] website: update docs for --install-provider flag

---
 website/docs/source/v2/cli/up.html.md | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/website/docs/source/v2/cli/up.html.md b/website/docs/source/v2/cli/up.html.md
index a0408a9a6..44d320669 100644
--- a/website/docs/source/v2/cli/up.html.md
+++ b/website/docs/source/v2/cli/up.html.md
@@ -20,6 +20,10 @@ on a day-to-day basis.
   unexpected error occurs. This will only happen on the first `vagrant up`.
   By default this is set.
 
+* `--[no-]install-provider` - If the requested provider is not installed,
+  Vagrant will attempt to automatically install it if it can. By default this
+  is enabled.
+
 * `--[no-]parallel` - Bring multiple machines up in parallel if the provider
   supports it. Please consult the provider documentation to see if this feature
   is supported.