providers/virtualbox: cap to read forwarded ports

plugins/providers/virtualbox/cap.rb

@@ -0,0 +1,20 @@
+module VagrantPlugins
+  module ProviderVirtualBox
+    module Cap
+      # Reads the forwarded ports that currently exist on the machine
+      # itself. This raises an exception if the machine isn't running.
+      #
+      # This also may not match up with configured forwarded ports, because
+      # Vagrant auto port collision fixing may have taken place.
+      #
+      # @return [Hash<Integer, Integer>] Host => Guest port mappings.
+      def self.forwarded_ports(machine)
+        {}.tap do |result|
+          machine.provider.driver.read_forwarded_ports.each do |_, _, h, g|
+            result[h] = g
+          end
+        end
+      end
+    end
+  end
+end

plugins/providers/virtualbox/plugin.rb

@@ -23,6 +23,11 @@ module VagrantPlugins
         require File.expand_path("../synced_folder", __FILE__)
         SyncedFolder
       end
+
+      provider_capability(:virtualbox, :forwarded_ports) do
+        require_relative "cap"
+        Cap
+      end
     end
 
     autoload :Action, File.expand_path("../action", __FILE__)

test/unit/plugins/providers/virtualbox/cap_test.rb

@@ -0,0 +1,36 @@
+require_relative "base"
+
+require Vagrant.source_root.join("plugins/providers/virtualbox/cap")
+
+describe VagrantPlugins::ProviderVirtualBox::Cap do
+  include_context "unit"
+
+  let(:iso_env) do
+    # We have to create a Vagrantfile so there is a root path
+    env = isolated_environment
+    env.vagrantfile("")
+    env.create_vagrant_env
+  end
+
+  let(:machine) do
+    iso_env.machine(iso_env.machine_names[0], :dummy).tap do |m|
+      m.provider.stub(driver: driver)
+    end
+  end
+
+  let(:driver) { double("driver") }
+
+  describe "#forwarded_ports" do
+    it "returns all the forwarded ports" do
+      driver.should_receive(:read_forwarded_ports).and_return([
+        [nil, nil, 123, 456],
+        [nil, nil, 245, 245],
+      ])
+
+      expect(described_class.forwarded_ports(machine)).to eq({
+        123 => 456,
+        245 => 245,
+      })
+    end
+  end
+end