support compression

README.md

@@ -212,6 +212,10 @@ to a single process.
         to (`['polling', 'websocket']`)
       - `allowUpgrades` (`Boolean`): whether to allow transport upgrades
         (`true`)
+      - `perMessageDeflate` (`Object|Boolean`): paramters of the WebSocket permessage-deflate extension
+        (see [ws module](https://github.com/einaros/ws) api docs). Set to `false` to disable. (`true`)
+      - `httpCompression` (`Object|Boolean`): paramters of the http compression for the polling transports
+        (see [zlib](http://nodejs.org/api/zlib.html#zlib_options) api docs). Set to `false` to disable. (`true`)
       - `cookie` (`String|Boolean`): name of the HTTP cookie that
         contains the client sid to send as part of handshake response
         headers. Set to `false` to not send one. (`io`)
@@ -297,7 +301,10 @@ A representation of a client. _Inherits from EventEmitter_.
       sending binary data, which is sent as is.
     - **Parameters**
       - `String` | `Buffer` | `ArrayBuffer` | `ArrayBufferView`: a string or any object implementing `toString()`, with outgoing data, or a Buffer or ArrayBuffer with binary data. Also any ArrayBufferView can be sent as is.
+      - `Object`: optional, options object
       - `Function`: optional, a callback executed when the message gets flushed out by the transport
+    - **Options**
+      - `compress` (`Boolean`): whether to compress sending data. This option might be ignored and forced to be `true` when using polling. (`true`)
     - **Returns** `Socket` for chaining
 - `close`
     - Disconnects the client

lib/server.js

@@ -44,10 +44,16 @@ function Server(opts){
   this.allowUpgrades = false !== opts.allowUpgrades;
   this.allowRequest = opts.allowRequest;
   this.cookie = false !== opts.cookie ? (opts.cookie || 'io') : false;
+  this.perMessageDeflate = opts.perMessageDeflate;
+  this.httpCompression = false !== opts.httpCompression ? (opts.httpCompression || true) : false;
 
   // initialize websocket server
   if (~this.transports.indexOf('websocket')) {
-    this.ws = new WebSocketServer({ noServer: true, clientTracking: false });
+    this.ws = new WebSocketServer({
+      noServer: true,
+      clientTracking: false,
+      perMessageDeflate: this.perMessageDeflate
+    });
   }
 }
 
@@ -228,6 +234,7 @@ Server.prototype.handshake = function(transport, req){
     var transport = new transports[transport](req);
     if ('polling' == transportName) {
       transport.maxHttpBufferSize = this.maxHttpBufferSize;
+      transport.httpCompression = true !== this.httpCompression ? this.httpCompression : {};
     }
 
     if (req._query && req._query.b64) {

lib/socket.js

@@ -280,14 +280,15 @@ Socket.prototype.setupSendCallback = function () {
  * Sends a message packet.
  *
  * @param {String} message
+ * @param {Object} options
  * @param {Function} callback
  * @return {Socket} for chaining
  * @api public
  */
 
 Socket.prototype.send =
-Socket.prototype.write = function(data, callback){
-  this.sendPacket('message', data, callback);
+Socket.prototype.write = function(data, options, callback){
+  this.sendPacket('message', data, options, callback);
   return this;
 };
 
@@ -296,15 +297,22 @@ Socket.prototype.write = function(data, callback){
  *
  * @param {String} packet type
  * @param {String} optional, data
+ * @param {Object} options
  * @api private
  */
 
-Socket.prototype.sendPacket = function (type, data, callback) {
+Socket.prototype.sendPacket = function (type, data, options, callback) {
+  if ('function' == typeof options) {
+    callback = options;
+    options = null;
+  }
+
   if ('closing' != this.readyState) {
     debug('sending packet "%s" (%s)', type, data);
 
     var packet = { type: type };
     if (data) packet.data = data;
+    if (options) packet.options = options;
 
     // exports packetCreate event
     this.emit('packetCreate', packet);

lib/transports/polling-jsonp.js

@@ -60,7 +60,7 @@ JSONP.prototype.onData = function (data) {
  * @api private
  */
 
-JSONP.prototype.doWrite = function (data) {
+JSONP.prototype.doWrite = function (data, options, callback) {
   // we must output valid javascript, not valid json
   // see: http://timelessrepo.com/json-isnt-a-javascript-subset
   var js = JSON.stringify(data)
@@ -70,21 +70,7 @@ JSONP.prototype.doWrite = function (data) {
   // prepare response
   data = this.head + js + this.foot;
 
-  // explicit UTF-8 is required for pages not served under utf
-  var headers = {
-    'Content-Type': 'text/javascript; charset=UTF-8',
-    'Content-Length': Buffer.byteLength(data)
-  };
-
-  // prevent XSS warnings on IE
-  // https://github.com/LearnBoost/socket.io/pull/1333
-  var ua = this.req.headers['user-agent'];
-  if (ua && (~ua.indexOf(';MSIE') || ~ua.indexOf('Trident/'))) {
-    headers['X-XSS-Protection'] = '0';
-  }
-
-  this.res.writeHead(200, this.headers(this.req, headers));
-  this.res.end(data);
+  Polling.prototype.doWrite.call(this, data, options, callback);
 };
 
 /**

lib/transports/polling-xhr.js

@@ -48,36 +48,6 @@ XHR.prototype.onRequest = function (req) {
   }
 };
 
-/**
- * Frames data prior to write.
- *
- * @api private
- */
-
-XHR.prototype.doWrite = function(data){
-  // explicit UTF-8 is required for pages not served under utf
-  var isString = typeof data == 'string';
-  var contentType = isString
-    ? 'text/plain; charset=UTF-8'
-    : 'application/octet-stream';
-  var contentLength = '' + (isString ? Buffer.byteLength(data) : data.length);
-
-  var headers = {
-    'Content-Type': contentType,
-    'Content-Length': contentLength
-  };
-
-  // prevent XSS warnings on IE
-  // https://github.com/LearnBoost/socket.io/pull/1333
-  var ua = this.req.headers['user-agent'];
-  if (ua && (~ua.indexOf(';MSIE') || ~ua.indexOf('Trident/'))) {
-    headers['X-XSS-Protection'] = '0';
-  }
-
-  this.res.writeHead(200, this.headers(this.req, headers));
-  this.res.end(data);
-};
-
 /**
  * Returns headers for a response.
  *

lib/transports/polling.js

@@ -5,8 +5,15 @@
 
 var Transport = require('../transport')
   , parser = require('engine.io-parser')
+  , zlib = require('zlib')
+  , accepts = require('accepts')
   , debug = require('debug')('engine:polling');
 
+var compressionMethods = {
+  gzip: zlib.createGzip,
+  deflate: zlib.createDeflate
+};
+
 /**
  * Exports the constructor.
  */
@@ -228,6 +235,8 @@ Polling.prototype.onClose = function () {
  */
 
 Polling.prototype.send = function (packets) {
+  this.writable = false;
+
   if (this.shouldClose) {
     debug('appending close packet to payload');
     packets.push({ type: 'close' });
@@ -237,22 +246,109 @@ Polling.prototype.send = function (packets) {
 
   var self = this;
   parser.encodePayload(packets, this.supportsBinary, function(data) {
-    self.write(data);
+    var compress = packets.some(function(packet) {
+      var options = packet.options || {};
+      return options.compress !== false;
+    });
+    self.write(data, { compress: compress });
   });
 };
 
 /**
  * Writes data as response to poll request.
  *
  * @param {String} data
+ * @param {Object} options
  * @api private
  */
 
-Polling.prototype.write = function (data) {
+Polling.prototype.write = function (data, options) {
   debug('writing "%s"', data);
-  this.doWrite(data);
-  this.req.cleanup();
-  this.writable = false;
+  var self = this;
+  this.doWrite(data, options, function() {
+    self.req.cleanup();
+  });
+};
+
+/**
+ * Performs the write.
+ *
+ * @api private
+ */
+
+Polling.prototype.doWrite = function (data, options, callback) {
+  var self = this;
+
+  // explicit UTF-8 is required for pages not served under utf
+  var isString = typeof data == 'string';
+  var contentType = isString
+    ? 'text/plain; charset=UTF-8'
+    : 'application/octet-stream';
+
+  var headers = {
+    'Content-Type': contentType
+  };
+
+  // prevent XSS warnings on IE
+  // https://github.com/LearnBoost/socket.io/pull/1333
+  var ua = this.req.headers['user-agent'];
+  if (ua && (~ua.indexOf(';MSIE') || ~ua.indexOf('Trident/'))) {
+    headers['X-XSS-Protection'] = '0';
+  }
+
+  if (!this.httpCompression || !options.compress) {
+    respond(data);
+    return;
+  }
+
+  var encoding = accepts(this.req).encodings(['gzip', 'deflate']);
+  if (!encoding) {
+    respond(data);
+    return;
+  }
+
+  this.compress(data, encoding, function(err, data) {
+    if (err) {
+      self.res.writeHead(500);
+      self.res.end();
+      callback(err);
+      return;
+    }
+
+    headers['Content-Encoding'] = encoding;
+    respond(data);
+  });
+
+  function respond(data) {
+    headers['Content-Length'] = 'string' == typeof data ? Buffer.byteLength(data) : data.length;
+    self.res.writeHead(200, self.headers(self.req, headers));
+    self.res.end(data);
+    callback();
+  }
+};
+
+/**
+ * Comparesses data.
+ *
+ * @api private
+ */
+
+Polling.prototype.compress = function (data, encoding, callback) {
+  debug('compressing');
+
+  var buffers = [];
+  var nread = 0;
+
+  compressionMethods[encoding](this.httpCompression)
+    .on('error', callback)
+    .on('data', function(chunk) {
+      buffers.push(chunk);
+      nread += chunk.length;
+    })
+    .on('end', function() {
+      callback(null, Buffer.concat(buffers, nread));
+    })
+    .end(data);
 };
 
 /**

lib/transports/websocket.js

@@ -85,10 +85,11 @@ WebSocket.prototype.onData = function (data) {
 WebSocket.prototype.send = function (packets) {
   var self = this;
   for (var i = 0, l = packets.length; i < l; i++) {
-    parser.encodePacket(packets[i], this.supportsBinary, function(data) {
+    var packet = packets[i];
+    parser.encodePacket(packet, this.supportsBinary, function(data) {
       debug('writing "%s"', data);
       self.writable = false;
-      self.socket.send(data, function (err){
+      self.socket.send(data, packet.options, function (err){
         if (err) return self.onError('write error', err.stack);
         self.writable = true;
         self.emit('drain');

package.json

@@ -17,9 +17,10 @@
   ],
   "dependencies": {
     "debug": "1.0.3",
-    "ws": "0.5.0",
+    "ws": "0.6.3",
     "engine.io-parser": "1.1.0",
-    "base64id": "0.1.0"
+    "base64id": "0.1.0",
+    "accepts": "1.1.4"
   },
   "devDependencies": {
     "mocha": "1.12.0",