Reads of Vagrant::ActiveList to track the active vagrant managed virtual environments.

lib/vagrant/active_list.rb

@@ -0,0 +1,40 @@
+module Vagrant
+  # This class represents the active list of vagrant virtual
+  # machines.
+  class ActiveList
+    FILENAME = "active.json"
+
+    @@list = nil
+
+    class <<self
+      # Parses and returns the list of UUIDs from the active VM
+      # JSON file. This will cache the result, which can be reloaded
+      # by setting the `reload` parameter to true.
+      #
+      # @return [Array<String>]
+      def list(reload = false)
+        return @@list unless @@list.nil? || reload
+
+        @@list ||= []
+        return @@list unless File.file?(path)
+        File.open(path, "r") do |f|
+          @@list = JSON.parse(f.read)
+        end
+
+        @@list
+      end
+
+      # Returns an array of {Vagrant::VM} objects which are currently
+      # active.
+      def vms
+        list.collect { |uuid| Vagrant::VM.find(uuid) }
+      end
+
+      # Returns the path to the JSON file which holds the UUIDs of the
+      # active virtual machines managed by Vagrant.
+      def path
+        File.join(Env.home_path, FILENAME)
+      end
+    end
+  end
+end

test/vagrant/active_list_test.rb

@@ -0,0 +1,71 @@
+require File.join(File.dirname(__FILE__), '..', 'test_helper')
+
+class ActiveListTest < Test::Unit::TestCase
+  setup do
+    mock_config
+  end
+
+  context "class methods" do
+    context "loading" do
+      should "load if reload is given" do
+        File.stubs(:file?).returns(true)
+        File.expects(:open).once
+        Vagrant::ActiveList.list(true)
+      end
+
+      should "not load if the active json file doesn't exist" do
+        File.expects(:file?).with(Vagrant::ActiveList.path).returns(false)
+        File.expects(:open).never
+        assert_equal [], Vagrant::ActiveList.list(true)
+      end
+
+      should "parse the JSON by reading the file" do
+        file = mock("file")
+        data = mock("data")
+        result = mock("result")
+        File.expects(:file?).returns(true)
+        File.expects(:open).with(Vagrant::ActiveList.path, 'r').once.yields(file)
+        file.expects(:read).returns(data)
+        JSON.expects(:parse).with(data).returns(result)
+        assert_equal result, Vagrant::ActiveList.list(true)
+      end
+
+      should "not load if reload flag is false and already loaded" do
+        File.expects(:file?).once.returns(false)
+        result = Vagrant::ActiveList.list(true)
+        assert result.equal?(Vagrant::ActiveList.list)
+        assert result.equal?(Vagrant::ActiveList.list)
+        assert result.equal?(Vagrant::ActiveList.list)
+      end
+    end
+
+    context "vms" do
+      setup do
+        @list = ["foo", "bar"]
+        Vagrant::ActiveList.stubs(:list).returns(@list)
+      end
+
+      should "return the list, but with each value as a VM" do
+        new_seq = sequence("new")
+        results = []
+        @list.each do |item|
+          result = mock("result-#{item}")
+          Vagrant::VM.expects(:find).with(item).returns(result).in_sequence(new_seq)
+          results << result
+        end
+
+        assert_equal results, Vagrant::ActiveList.vms
+      end
+    end
+
+    context "path" do
+      setup do
+        Vagrant::Env.stubs(:home_path).returns("foo")
+      end
+
+      should "return the active file within the home path" do
+        assert_equal File.join(Vagrant::Env.home_path, Vagrant::ActiveList::FILENAME), Vagrant::ActiveList.path
+      end
+    end
+  end
+end