NFS middleware interface complete. Implemention on host not yet done.

lib/vagrant/action/vm/nfs.rb

@@ -14,7 +14,7 @@ module Vagrant
       #      folder.
       #
       class NFS
-        attr_reader :folders
+        include ExceptionCatcher
 
         def initialize(app,env)
           @app = app
@@ -27,9 +27,17 @@ module Vagrant
           @env = env
 
           extract_folders
-          export_folders
+          export_folders if !folders.empty?
+          return if env.error?
 
           @app.call(env)
+
+          mount_folders if !folders.empty? && !env.error?
+        end
+
+        # Returns the folders which are to be synced via NFS.
+        def folders
+          @folders ||= {}
         end
 
         # Removes the NFS enabled shared folders from the configuration,
@@ -54,6 +62,13 @@ module Vagrant
         # involves adding a line to `/etc/exports` for this VM, but it is
         # up to the host class to define the specific behavior.
         def export_folders
+          catch_action_exception(@env) do
+            @env["host"].nfs_export(folders)
+          end
+        end
+
+        # Uses the system class to mount the NFS folders.
+        def mount_folders
         end
 
         # Verifies that the host is set and supports NFS.

lib/vagrant/hosts/base.rb

@@ -59,6 +59,13 @@ module Vagrant
       def nfs?
         false
       end
+
+      # Exports the given hash of folders via NFS. This method will raise
+      # an {Vagrant::Action::ActionException} if anything goes wrong.
+      #
+      # @param [Hash] folders Shared folders to sync.
+      def nfs_export(folders)
+      end
     end
   end
 end

test/vagrant/action/vm/nfs_test.rb

@@ -22,11 +22,53 @@ class NFSVMActionTest < Test::Unit::TestCase
     end
 
     context "calling" do
+      setup do
+        @instance.stubs(:folders).returns([:a])
+
+        [:extract_folders, :export_folders, :mount_folders].each do |meth|
+          @instance.stubs(meth)
+        end
+      end
+
       should "call the proper sequence and succeed" do
         seq = sequence('seq')
         @instance.expects(:extract_folders).in_sequence(seq)
         @instance.expects(:export_folders).in_sequence(seq)
         @app.expects(:call).with(@env).in_sequence(seq)
+        @instance.expects(:mount_folders).in_sequence(seq)
+        @instance.call(@env)
+      end
+
+      should "not export folders if folders is empty" do
+        @instance.stubs(:folders).returns([])
+
+        seq = sequence('seq')
+        @instance.expects(:extract_folders).in_sequence(seq)
+        @instance.expects(:export_folders).never
+        @app.expects(:call).with(@env).in_sequence(seq)
+        @instance.expects(:mount_folders).never
+        @instance.call(@env)
+      end
+
+      should "halt chain if environment error occured" do
+        @env.error!(:foo)
+
+        seq = sequence('seq')
+        @instance.expects(:extract_folders).in_sequence(seq)
+        @instance.expects(:export_folders).in_sequence(seq)
+        @app.expects(:call).never
+        @instance.call(@env)
+      end
+
+      should "not mount folders if an error occured" do
+        @app.expects(:call).with() do
+          # Use this mark the env as error
+          @env.error!(:foo)
+
+          true
+        end
+
+        @instance.expects(:mount_folders).never
         @instance.call(@env)
       end
     end
@@ -49,6 +91,24 @@ class NFSVMActionTest < Test::Unit::TestCase
       end
     end
 
+    context "exporting folders" do
+      setup do
+        @instance.stubs(:folders).returns({})
+      end
+
+      should "call nfs_export on the host" do
+        @env["host"].expects(:nfs_export).with(@instance.folders)
+        @instance.export_folders
+      end
+
+      should "error the environment if exception is raised" do
+        @env["host"].expects(:nfs_export).raises(Vagrant::Action::ActionException.new(:foo))
+        @instance.export_folders
+        assert @env.error?
+        assert_equal :foo, @env.error.first
+      end
+    end
+
     context "verifying host" do
       should "error environment if host is nil" do
         @env.env.stubs(:host).returns(nil)