BatchAction for running actions in parallel

lib/vagrant.rb

@@ -64,6 +64,7 @@ require "vagrant/registry"
 
 module Vagrant
   autoload :Action,        'vagrant/action'
+  autoload :BatchAction,   'vagrant/batch_action'
   autoload :Box,           'vagrant/box'
   autoload :BoxCollection, 'vagrant/box_collection'
   autoload :CLI,           'vagrant/cli'

lib/vagrant/batch_action.rb

@@ -0,0 +1,41 @@
+require 'thread'
+
+require "log4r"
+
+module Vagrant
+  # This class executes multiple actions as a single batch, parallelizing
+  # the action calls if possible.
+  class BatchAction
+    def initialize
+      @actions = []
+      @logger  = Log4r::Logger.new("vagrant::batch_action")
+    end
+
+    def action(machine, action, options=nil)
+      @actions << [machine, action, options]
+    end
+
+    def run
+      par = true
+      @actions.each do |machine, _, _|
+        if !machine.provider_options[:parallel]
+          par = false
+          break
+        end
+      end
+
+      @logger.info("Batch action will parallelize: #{par.inspect}")
+
+      threads = []
+      @actions.each do |machine, action, options|
+        @logger.info("Starting action: #{machine} #{action} #{options}")
+
+        thread = Thread.new { machine.send(:action, action, options) }
+        thread.join if !par
+        threads << thread
+      end
+
+      threads.map(&:join)
+    end
+  end
+end

test/unit/vagrant/batch_action_test.rb

@@ -0,0 +1,34 @@
+require 'thread'
+
+require File.expand_path("../../base", __FILE__)
+
+describe Vagrant::BatchAction do
+  let(:called_actions) { [] }
+  let!(:lock) { Mutex.new }
+  let(:provider_options) { {} }
+
+  def new_machine(options)
+    double("machine").tap do |m|
+      m.stub(:provider_options => options)
+      m.stub(:action) do |action, opts|
+        lock.synchronize do
+          called_actions << [m, action, opts]
+        end
+      end
+    end
+  end
+
+  describe "#run" do
+    let(:machine) { new_machine(provider_options) }
+    let(:machine2) { new_machine(provider_options) }
+
+    it "should run the actions on the machines in order" do
+      subject.action(machine, "up")
+      subject.action(machine2, "destroy")
+      subject.run
+
+      called_actions.include?([machine, "up", nil]).should be
+      called_actions.include?([machine2, "destroy", nil]).should be
+    end
+  end
+end