Move hosts to a plugin system

lib/vagrant.rb

@@ -114,16 +114,6 @@ module Vagrant
   def self.commands
     @commands ||= Registry.new
   end
-
-  # Global registry of available host classes and shortcut symbols
-  # associated with them.
-  #
-  # This registry is used to look up the shorcuts for `config.vagrant.host`,
-  # or to query all hosts for automatically detecting the host system.
-  # The registry is global to all of Vagrant.
-  def self.hosts
-    @hosts ||= Registry.new
-  end
 end
 
 # # Default I18n to load the en locale
@@ -157,13 +147,3 @@ Vagrant.commands.register(:"ssh-config") { Vagrant::Command::SSHConfig }
 Vagrant.commands.register(:status)       { Vagrant::Command::Status }
 Vagrant.commands.register(:suspend)      { Vagrant::Command::Suspend }
 Vagrant.commands.register(:up)           { Vagrant::Command::Up }
-
-# Register the built-in hosts
-Vagrant.hosts.register(:arch)    { Vagrant::Hosts::Arch }
-Vagrant.hosts.register(:bsd)     { Vagrant::Hosts::BSD }
-Vagrant.hosts.register(:fedora)  { Vagrant::Hosts::Fedora }
-Vagrant.hosts.register(:opensuse)  { Vagrant::Hosts::OpenSUSE }
-Vagrant.hosts.register(:freebsd) { Vagrant::Hosts::FreeBSD }
-Vagrant.hosts.register(:gentoo)  { Vagrant::Hosts::Gentoo }
-Vagrant.hosts.register(:linux)   { Vagrant::Hosts::Linux }
-Vagrant.hosts.register(:windows) { Vagrant::Hosts::Windows }

lib/vagrant/environment.rb

@@ -178,7 +178,15 @@ module Vagrant
       # check is done after the detect check because the symbol check
       # will return nil, and we don't want to trigger a detect load.
       host_klass = config.global.vagrant.host
-      host_klass = Hosts.detect(Vagrant.hosts) if host_klass.nil? || host_klass == :detect
+      if host_klass.nil? || host_klass == :detect
+        hosts = {}
+        Vagrant.plugin("1").registered.each do |plugin|
+          hosts = hosts.merge(plugin.host.to_hash)
+        end
+
+        # Get the flattened list of available hosts
+        host_klass = Hosts.detect(hosts)
+      end
       host_klass = Vagrant.hosts.get(host_klass) if host_klass.is_a?(Symbol)
 
       # If no host class is detected, we use the base class.

lib/vagrant/hosts.rb

@@ -14,12 +14,13 @@ module Vagrant
 
     # This method detects the correct host based on the `match?` methods
     # implemented in the registered hosts.
+    #
+    # @param [Hash] registry Hash mapping key to host class
     def self.detect(registry)
       logger = Log4r::Logger.new("vagrant::hosts")
 
       # Sort the hosts by their precedence
-      host_klasses = registry.to_hash.values
-      host_klasses = host_klasses.sort_by { |a| a.precedence }.reverse
+      host_klasses = registry.values.sort_by { |a| a.precedence }.reverse
       logger.debug("Host path search classes: #{host_klasses.inspect}")
 
       # Test for matches and return the host class that matches

lib/vagrant/plugin/v1.rb

@@ -72,6 +72,20 @@ module Vagrant
         data[:guests]
       end
 
+      # Defines an additionally available host implementation with
+      # the given key.
+      #
+      # @param [String] name Name of the host.
+      def self.host(name=UNSET_VALUE, &block)
+        data[:hosts] ||= Registry.new
+
+        # Register a new host class only if a name was given
+        data[:hosts].register(name.to_sym, &block) if name != UNSET_VALUE
+
+        # Return the registry
+        data[:hosts]
+      end
+
       # Registers additional provisioners to be available.
       #
       # @param [String] name Name of the provisioner.

plugins/host_arch/host.rb

@@ -1,6 +1,6 @@
-module Vagrant
-  module Hosts
-    class Arch < Linux
+module VagrantPlugins
+  module HostArch
+    class Host < VagrantPlugins::HostLinux::Host
       def self.match?
         File.exist?("/etc/rc.conf") && File.exist?("/etc/pacman.conf")
       end

plugins/host_arch/plugin.rb

@@ -0,0 +1,14 @@
+require "vagrant"
+
+module VagrantPlugins
+  module HostArch
+    autoload :Host, File.expand_path("../host", __FILE__)
+
+    class Plugin < Vagrant.plugin("1")
+      name "Arch host"
+      description "Arch host support."
+
+      host("arch") { Host }
+    end
+  end
+end

plugins/host_bsd/host.rb

@@ -2,15 +2,15 @@ require 'log4r'
 
 require 'vagrant/util/platform'
 
-module Vagrant
-  module Hosts
+module VagrantPlugins
+  module HostBSD
     # Represents a BSD host, such as FreeBSD and Darwin (Mac OS X).
-    class BSD < Base
-      include Util
-      include Util::Retryable
+    class Host < Vagrant::Hosts::Base
+      include Vagrant::Util
+      include Vagrant::Util::Retryable
 
       def self.match?
-        Util::Platform.darwin? || Util::Platform.bsd?
+        Vagrant::Util::Platform.darwin? || Vagrant::Util::Platform.bsd?
       end
 
       def self.precedence

plugins/host_bsd/plugin.rb

@@ -0,0 +1,14 @@
+require "vagrant"
+
+module VagrantPlugins
+  module HostBSD
+    autoload :Host, File.expand_path("../host", __FILE__)
+
+    class Plugin < Vagrant.plugin("1")
+      name "BSD host"
+      description "BSD host support."
+
+      host("bsd") { Host }
+    end
+  end
+end

plugins/host_fedora/host.rb

@@ -1,8 +1,8 @@
-require 'pathname'
+require "pathname"
 
-module Vagrant
-  module Hosts
-    class Fedora < Linux
+module VagrantPlugins
+  module HostFedora
+    class Host < VagrantPlugins::HostLinux::Host
       def self.match?
         release_file = Pathname.new("/etc/redhat-release")
 

plugins/host_fedora/plugin.rb

@@ -0,0 +1,14 @@
+require "vagrant"
+
+module VagrantPlugins
+  module HostFedora
+    autoload :Host, File.expand_path("../host", __FILE__)
+
+    class Plugin < Vagrant.plugin("1")
+      name "Fedora host"
+      description "Fedora host support."
+
+      host("fedora") { Host }
+    end
+  end
+end

plugins/host_freebsd/host.rb

@@ -1,18 +1,17 @@
 require 'vagrant/util/platform'
 
-module Vagrant
-  module Hosts
-    # Represents a FreeBSD host
-    class FreeBSD < BSD
-      class FreeBSDHostError < Errors::VagrantError
+module VagrantPlugins
+  module HostFreeBSD
+    class Host < VagrantPlugins::HostBSD::Host
+      class FreeBSDHostError < Vagrant::Errors::VagrantError
         error_namespace("vagrant.hosts.freebsd")
       end
 
-      include Util
-      include Util::Retryable
+      include Vagrant::Util
+      include Vagrant::Util::Retryable
 
       def self.match?
-        Util::Platform.freebsd?
+        Vagrant::Util::Platform.freebsd?
       end
 
       # Normal, mid-range precedence.

plugins/host_freebsd/plugin.rb

@@ -0,0 +1,14 @@
+require "vagrant"
+
+module VagrantPlugins
+  module HostFreeBSD
+    autoload :Host, File.expand_path("../host", __FILE__)
+
+    class Plugin < Vagrant.plugin("1")
+      name "FreeBSD host"
+      description "FreeBSD host support."
+
+      host("freebsd") { Host }
+    end
+  end
+end

plugins/host_gentoo/host.rb

@@ -1,6 +1,6 @@
-module Vagrant
-  module Hosts
-    class Gentoo < Linux
+module VagrantPlugins
+  module HostGentoo
+    class Host < VagrantPlugins::HostLinux::Host
       def self.match?
         return File.exists?("/etc/gentoo-release")
       end

plugins/host_gentoo/plugin.rb

@@ -0,0 +1,14 @@
+require "vagrant"
+
+module VagrantPlugins
+  module HostGentoo
+    autoload :Host, File.expand_path("../host", __FILE__)
+
+    class Plugin < Vagrant.plugin("1")
+      name "Gentoo host"
+      description "Gentoo host support."
+
+      host("gentoo") { Host }
+    end
+  end
+end

plugins/host_linux/host.rb

@@ -2,15 +2,15 @@ require 'log4r'
 
 require 'vagrant/util/platform'
 
-module Vagrant
-  module Hosts
+module VagrantPlugins
+  module HostLinux
     # Represents a Linux based host, such as Ubuntu.
-    class Linux < Base
-      include Util
-      include Util::Retryable
+    class Host < Vagrant::Hosts::Base
+      include Vagrant::Util
+      include Vagrant::Util::Retryable
 
       def self.match?
-        Util::Platform.linux?
+        Vagrant::Util::Platform.linux?
       end
 
       def self.precedence

plugins/host_linux/plugin.rb

@@ -0,0 +1,14 @@
+require "vagrant"
+
+module VagrantPlugins
+  module HostLinux
+    autoload :Host, File.expand_path("../host", __FILE__)
+
+    class Plugin < Vagrant.plugin("1")
+      name "Linux host"
+      description "Linux host support."
+
+      host("linux") { Host }
+    end
+  end
+end

plugins/host_opensuse/host.rb

@@ -1,8 +1,8 @@
-require 'pathname'
+require "pathname"
 
-module Vagrant
-  module Hosts
-    class OpenSUSE < Linux
+module VagrantPlugins
+  module HostOpenSUSE
+    class Host < VagrantPlugins::HostLinux::Host
       def self.match?
         release_file = Pathname.new("/etc/SuSE-release")
 

plugins/host_opensuse/plugin.rb

@@ -0,0 +1,14 @@
+require "vagrant"
+
+module VagrantPlugins
+  module HostOpenSUSE
+    autoload :Host, File.expand_path("../host", __FILE__)
+
+    class Plugin < Vagrant.plugin("1")
+      name "OpenSUSE host"
+      description "OpenSUSE host support."
+
+      host("opensuse") { Host }
+    end
+  end
+end

plugins/host_windows/host.rb

@@ -1,10 +1,10 @@
 require 'vagrant/util/platform'
 
-module Vagrant
-  module Hosts
-    class Windows < Base
+module VagrantPlugins
+  module HostWindows
+    class Host < Vagrant::Hosts::Base
       def self.match?
-        Util::Platform.windows?
+        Vagrant::Util::Platform.windows?
       end
 
       # Windows does not support NFS

plugins/host_windows/plugin.rb

@@ -0,0 +1,14 @@
+require "vagrant"
+
+module VagrantPlugins
+  module HostWindows
+    autoload :Host, File.expand_path("../host", __FILE__)
+
+    class Plugin < Vagrant.plugin("1")
+      name "Windows host"
+      description "Windows host support."
+
+      host("windows") { Host }
+    end
+  end
+end

test/unit/vagrant/hosts_test.rb

@@ -1,7 +1,7 @@
 require File.expand_path("../../base", __FILE__)
 
 describe Vagrant::Hosts do
-  let(:registry) { Vagrant::Registry.new }
+  let(:registry) { Hash.new }
 
   it "detects the host that matches true" do
     foo_klass = Class.new(Vagrant::Hosts::Base) do
@@ -12,8 +12,8 @@ describe Vagrant::Hosts do
       def self.match?; true; end
     end
 
-    registry.register(:foo, foo_klass)
-    registry.register(:bar, bar_klass)
+    registry[:foo] = foo_klass
+    registry[:bar] = bar_klass
 
     described_class.detect(registry).should == bar_klass
   end
@@ -28,8 +28,8 @@ describe Vagrant::Hosts do
       def self.precedence; 9; end
     end
 
-    registry.register(:foo, foo_klass)
-    registry.register(:bar, bar_klass)
+    registry[:foo] = foo_klass
+    registry[:bar] = bar_klass
 
     described_class.detect(registry).should == bar_klass
   end

test/unit/vagrant/plugin/v1_test.rb

@@ -60,8 +60,8 @@ describe Vagrant::Plugin::V1 do
       plugin.guest[:foo].should == "bar"
     end
 
-    it "should lazily register configuration classes" do
-      # Below would raise an error if the value of the config class was
+    it "should lazily register guest classes" do
+      # Below would raise an error if the value of the guest class was
       # evaluated immediately. By asserting that this does not raise an
       # error, we verify that the value is actually lazily loaded
       plugin = nil
@@ -71,7 +71,7 @@ describe Vagrant::Plugin::V1 do
         end
       }.to_not raise_error
 
-      # Now verify when we actually get the configuration key that
+      # Now verify when we actually get the guest key that
       # a proper error is raised.
       expect {
         plugin.guest[:foo]
@@ -79,6 +79,34 @@ describe Vagrant::Plugin::V1 do
     end
   end
 
+  describe "hosts" do
+    it "should register host classes" do
+      plugin = Class.new(described_class) do
+        host("foo") { "bar" }
+      end
+
+      plugin.host[:foo].should == "bar"
+    end
+
+    it "should lazily register host classes" do
+      # Below would raise an error if the value of the host class was
+      # evaluated immediately. By asserting that this does not raise an
+      # error, we verify that the value is actually lazily loaded
+      plugin = nil
+      expect {
+        plugin = Class.new(described_class) do
+          host("foo") { raise StandardError, "FAIL!" }
+        end
+      }.to_not raise_error
+
+      # Now verify when we actually get the host key that
+      # a proper error is raised.
+      expect {
+        plugin.host[:foo]
+      }.to raise_error(StandardError)
+    end
+  end
+
   describe "provisioners" do
     it "should register provisioner classes" do
       plugin = Class.new(described_class) do

test/unit/vagrant_test.rb

@@ -9,10 +9,6 @@ describe Vagrant do
     described_class.commands.should be_a(Vagrant::Registry)
   end
 
-  it "has a registry for hosts" do
-    described_class.hosts.should be_a(Vagrant::Registry)
-  end
-
   describe "plugin superclass" do
     it "returns the proper class for version 1" do
       described_class.plugin("1").should == Vagrant::Plugin::V1