From d927b400bd8acd6399dff9bc636703c97d22cbf3 Mon Sep 17 00:00:00 2001
From: NumminorihSF <numminorihsf@gmail.com>
Date: Mon, 11 Jan 2016 14:22:05 +0700
Subject: [PATCH 1/2] add heartbeat

---
 lib/client.js                |  3 ++-
 lib/connection-parameters.js |  2 ++
 lib/connection.js            | 15 +++++++++++++++
 lib/defaults.js              |  6 +++++-
 4 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/lib/client.js b/lib/client.js
index f0a374d32..fd5906444 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -25,7 +25,8 @@ var Client = function(config) {
 
   this.connection = c.connection || new Connection({
     stream: c.stream,
-    ssl: this.connectionParameters.ssl
+    ssl: this.connectionParameters.ssl,
+    heartbeat: this.connectionParameters.heartbeatInterval
   });
   this.queryQueue = [];
   this.binary = c.binary || defaults.binary;
diff --git a/lib/connection-parameters.js b/lib/connection-parameters.js
index 2ba462bbb..5fcfc3d2f 100644
--- a/lib/connection-parameters.js
+++ b/lib/connection-parameters.js
@@ -48,6 +48,8 @@ var ConnectionParameters = function(config) {
 
   this.application_name = val('application_name', config, 'PGAPPNAME');
   this.fallback_application_name = val('fallback_application_name', config, false);
+
+  this.heartbeatInterval = parseInt(val('heartbeat_interval', config), 10);
 };
 
 var add = function(params, config, paramName) {
diff --git a/lib/connection.js b/lib/connection.js
index f606de136..505305f08 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -26,6 +26,9 @@ var Connection = function(config) {
     headerSize: 1,
     lengthPadding: -4
   });
+  this._heartbeatEnable = !!config.heartbeat;
+  this._heartbeatInterval = Number(config.heartbeat);
+  this._heartbeatObject = null;
   var self = this;
   this.on('newListener', function(eventName) {
     if(eventName == 'message') {
@@ -48,6 +51,16 @@ Connection.prototype.connect = function(port, host) {
 
   this.stream.on('connect', function() {
     self.emit('connect');
+    if (self._heartbeatEnable) {
+      self._heartbeatObject = setInterval(function() {
+        self.stream.write('', function (err) {
+          if (err) {
+            clearInterval(self._heartbeatObject);
+            self.emit('error', err);
+          }
+        })
+      }, self._heartbeatInterval);
+    }
   });
 
   this.stream.on('error', function(error) {
@@ -56,6 +69,7 @@ Connection.prototype.connect = function(port, host) {
     if(self._ending && error.code == 'ECONNRESET') {
       return;
     }
+    clearInterval(self._heartbeatObject);
     self.emit('error', error);
   });
 
@@ -63,6 +77,7 @@ Connection.prototype.connect = function(port, host) {
     // NOTE: node-0.10 emits both 'end' and 'close'
     //       for streams closed by the peer, while
     //       node-0.8 only emits 'close'
+    clearInterval(self._heartbeatObject);
     self.emit('end');
   });
 
diff --git a/lib/defaults.js b/lib/defaults.js
index d3cb911a4..8b27fc83f 100644
--- a/lib/defaults.js
+++ b/lib/defaults.js
@@ -41,7 +41,11 @@ var defaults = module.exports = {
   ssl: false,
 
   application_name : undefined,
-  fallback_application_name: undefined
+  fallback_application_name: undefined,
+
+  //heartbeat interval to check, that socket is alive. if 0 - heartbeat is disabled (for backward capability).
+  //else - timeout in ms.
+  heartbeat_interval: 0
 };
 
 //parse int8 so you can get your count values as actual numbers

From eb9727aaceee70cd03fceabfe9651633143d9557 Mon Sep 17 00:00:00 2001
From: NumminorihSF <numminorihsf@gmail.com>
Date: Mon, 11 Jan 2016 14:38:28 +0700
Subject: [PATCH 2/2] add semicolon

---
 lib/connection.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/connection.js b/lib/connection.js
index 505305f08..c8f736543 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -58,7 +58,7 @@ Connection.prototype.connect = function(port, host) {
             clearInterval(self._heartbeatObject);
             self.emit('error', err);
           }
-        })
+        });
       }, self._heartbeatInterval);
     }
   });