remove listeners upon clearTransport

Author: nkzawa

lib/socket.js

@@ -26,6 +26,7 @@ function Socket (id, server, transport, req) {
   this.writeBuffer = [];
   this.packetsFn = [];
   this.sentCallbackFn = [];
+  this.cleanupFn = [];
   this.request = req;
 
   // Cache IP since it might not be in the req later
@@ -140,13 +141,25 @@ Socket.prototype.setPingTimeout = function () {
  */
 
 Socket.prototype.setTransport = function (transport) {
+  var onError = this.onError.bind(this);
+  var onPacket = this.onPacket.bind(this);
+  var flush = this.flush.bind(this);
+  var onClose = this.onClose.bind(this, 'transport close');
+
   this.transport = transport;
-  this.transport.once('error', this.onError.bind(this));
-  this.transport.on('packet', this.onPacket.bind(this));
-  this.transport.on('drain', this.flush.bind(this));
-  this.transport.once('close', this.onClose.bind(this, 'transport close'));
+  this.transport.once('error', onError);
+  this.transport.on('packet', onPacket);
+  this.transport.on('drain', flush);
+  this.transport.once('close', onClose);
   //this function will manage packet events (also message callbacks)
   this.setupSendCallback();
+
+  this.cleanupFn.push(function() {
+    transport.removeListener('error', onError);
+    transport.removeListener('packet', onPacket);
+    transport.removeListener('drain', flush);
+    transport.removeListener('close', onClose);
+  });
 };
 
 /**
@@ -251,6 +264,9 @@ Socket.prototype.maybeUpgrade = function (transport) {
  */
 
 Socket.prototype.clearTransport = function () {
+  var cleanup;
+  while (cleanup = this.cleanupFn.shift()) cleanup();
+
   // silence further transport errors and prevent uncaught exceptions
   this.transport.on('error', function(){
     debug('error triggered by discarded transport');
@@ -296,8 +312,14 @@ Socket.prototype.onClose = function (reason, description) {
 
 Socket.prototype.setupSendCallback = function () {
   var self = this;
+  this.transport.on('drain', onDrain);
+
+  this.cleanupFn.push(function() {
+    self.transport.removeListener('drain', onDrain);
+  });
+
   //the message was sent successfully, execute the callback
-  this.transport.on('drain', function() {
+  function onDrain() {
     if (self.sentCallbackFn.length > 0) {
       var seqFn = self.sentCallbackFn.splice(0,1)[0];
       if ('function' == typeof seqFn) {
@@ -312,7 +334,7 @@ Socket.prototype.setupSendCallback = function () {
         }
       }
     }
-  });
+  }
 };
 
 /**