From 28a8293a22ed009774ba91383e9e6514d26784be Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Mon, 19 Aug 2013 16:25:00 -0700
Subject: [PATCH] packer/plugin: set TCP keep-alive on connection

---
 CHANGELOG.md            | 1 +
 packer/plugin/client.go | 9 +++++++--
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 33fa28d68..bbe27c5f1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -15,6 +15,7 @@ IMPROVEMENTS:
 
 BUG FIXES:
 
+* core: TCP connection between plugin processes will keep-alive. [GH-312]
 * core: No more "unused key keep_input_artifact" for post processors [GH-310]
 * post-processor/vagrant: `output_path` templates now work again.
 
diff --git a/packer/plugin/client.go b/packer/plugin/client.go
index e380bf850..94513a8e2 100644
--- a/packer/plugin/client.go
+++ b/packer/plugin/client.go
@@ -10,6 +10,7 @@ import (
 	"io"
 	"io/ioutil"
 	"log"
+	"net"
 	"net/rpc"
 	"os"
 	"os/exec"
@@ -328,10 +329,14 @@ func (c *Client) rpcClient() (*rpc.Client, error) {
 		return nil, err
 	}
 
-	client, err := rpc.Dial("tcp", address)
+	conn, err := net.Dial("tcp", address)
 	if err != nil {
 		return nil, err
 	}
 
-	return client, nil
+	// Make sure to set keep alive so that the connection doesn't die
+	tcpConn := conn.(*net.TCPConn)
+	tcpConn.SetKeepAlive(true)
+
+	return rpc.NewClient(tcpConn), nil
 }