From daa431af638d57d34dfcdfde35604417845f33ef Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Sun, 12 May 2013 16:25:40 -0700
Subject: [PATCH] packer: Communicator Upload/Download return an error

---
 packer/communicator.go          | 4 ++--
 packer/rpc/communicator.go      | 8 ++++++--
 packer/rpc/communicator_test.go | 8 ++++++--
 3 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/packer/communicator.go b/packer/communicator.go
index 57826298f..54df5b34b 100644
--- a/packer/communicator.go
+++ b/packer/communicator.go
@@ -13,8 +13,8 @@ import (
 // Start or any other method may be called at the same time.
 type Communicator interface {
 	Start(string) (*RemoteCommand, error)
-	Upload(string, io.Reader)
-	Download(string, io.Writer)
+	Upload(string, io.Reader) error
+	Download(string, io.Writer) error
 }
 
 // This struct contains some information about the remote command being
diff --git a/packer/rpc/communicator.go b/packer/rpc/communicator.go
index b7204f514..97d82360f 100644
--- a/packer/rpc/communicator.go
+++ b/packer/rpc/communicator.go
@@ -87,9 +87,13 @@ func (c *communicator) Start(cmd string) (rc *packer.RemoteCommand, err error) {
 	return
 }
 
-func (c *communicator) Upload(string, io.Reader) {}
+func (c *communicator) Upload(string, io.Reader) error {
+	return nil
+}
 
-func (c *communicator) Download(string, io.Writer) {}
+func (c *communicator) Download(string, io.Writer) error {
+	return nil
+}
 
 func (c *CommunicatorServer) Start(cmd *string, reply *CommunicatorStartResponse) (err error) {
 	// Start executing the command.
diff --git a/packer/rpc/communicator_test.go b/packer/rpc/communicator_test.go
index 34ea4a9a2..adcfbf2e6 100644
--- a/packer/rpc/communicator_test.go
+++ b/packer/rpc/communicator_test.go
@@ -45,9 +45,13 @@ func (t *testCommunicator) Start(cmd string) (*packer.RemoteCommand, error) {
 	return rc, nil
 }
 
-func (t *testCommunicator) Upload(string, io.Reader) {}
+func (t *testCommunicator) Upload(string, io.Reader) error {
+	return nil
+}
 
-func (t *testCommunicator) Download(string, io.Writer) {}
+func (t *testCommunicator) Download(string, io.Writer) error {
+	return nil
+}
 
 func TestCommunicatorRPC(t *testing.T) {
 	assert := asserts.NewTestingAsserts(t, true)