Merge pull request #698 from rib/binarytype

lib/WebSocket.js: expose binaryType property

Author: 3rd-Eden

lib/WebSocket.js

@@ -71,6 +71,7 @@ function WebSocket(address, protocols, options) {
   this.readyState = null;
   this.supports = {};
   this.extensions = {};
+  this._binaryType = 'nodebuffer';
 
   if (Array.isArray(address)) {
     initAsServerClient.apply(this, address.concat(options));
@@ -371,6 +372,27 @@ Object.defineProperty(WebSocket.prototype, 'bufferedAmount', {
   }
 });
 
+/**
+ * Expose binaryType
+ *
+ * This deviates from the W3C interface since ws doesn't support the required
+ * default "blob" type (instead we define a custom "nodebuffer" type).
+ *
+ * @see http://dev.w3.org/html5/websockets/#the-websocket-interface
+ * @api public
+ */
+Object.defineProperty(WebSocket.prototype, 'binaryType', {
+  get: function get() {
+    return this._binaryType;
+  },
+  set: function set(type) {
+    if (type === 'arraybuffer' || type === 'nodebuffer')
+      this._binaryType = type;
+    else
+      throw new SyntaxError('unsupported binaryType: must be either "nodebuffer" or "arraybuffer"');
+  }
+});
+
 /**
  * Emulates the W3C Browser based WebSocket interface using function members.
  *
@@ -415,6 +437,8 @@ WebSocket.prototype.addEventListener = function(method, listener) {
   var target = this;
 
   function onMessage (data, flags) {
+    if (flags.binary && this.binaryType === 'arraybuffer')
+        data = new Uint8Array(data).buffer;
     listener.call(target, new MessageEvent(data, !!flags.binary, target));
   }
 

test/WebSocket.test.js

@@ -1544,6 +1544,10 @@ describe('WebSocket', function() {
         ws.onclose = listener;
         ws.onopen = listener;
 
+        assert.ok(ws.binaryType === 'nodebuffer');
+        ws.binaryType = 'arraybuffer';
+        assert.ok(ws.binaryType === 'arraybuffer');
+
         assert.ok(ws.onopen === listener);
         assert.ok(ws.onmessage === listener);
         assert.ok(ws.onclose === listener);
@@ -1694,6 +1698,63 @@ describe('WebSocket', function() {
         client.send('hi')
       });
     });
+
+    it('should pass binary data as a node.js Buffer by default', function(done) {
+      server.createServer(++port, function(srv) {
+        var ws = new WebSocket('ws://localhost:' + port);
+        var array = new Uint8Array(4096);
+
+        ws.onopen = function() {
+          ws.send(array, {binary: true});
+        };
+        ws.onmessage = function(messageEvent) {
+          assert.ok(messageEvent.binary);
+          assert.ok(ws.binaryType === 'nodebuffer');
+          assert.ok(messageEvent.data instanceof Buffer);
+          ws.terminate();
+          srv.close();
+          done();
+        };
+      });
+    });
+
+    it('should pass an ArrayBuffer for event.data if binaryType = arraybuffer', function(done) {
+      server.createServer(++port, function(srv) {
+        var ws = new WebSocket('ws://localhost:' + port);
+        ws.binaryType = 'arraybuffer';
+        var array = new Uint8Array(4096);
+
+        ws.onopen = function() {
+          ws.send(array, {binary: true});
+        };
+        ws.onmessage = function(messageEvent) {
+          assert.ok(messageEvent.binary);
+          assert.ok(messageEvent.data instanceof ArrayBuffer);
+          ws.terminate();
+          srv.close();
+          done();
+        };
+      });
+    });
+
+    it('should ignore binaryType for text messages', function(done) {
+      server.createServer(++port, function(srv) {
+        var ws = new WebSocket('ws://localhost:' + port);
+        ws.binaryType = 'arraybuffer';
+
+        ws.onopen = function() {
+          ws.send('foobar');
+        };
+        ws.onmessage = function(messageEvent) {
+          assert.ok(!messageEvent.binary);
+          assert.ok(typeof messageEvent.data === 'string');
+          ws.terminate();
+          srv.close();
+          done();
+        };
+      });
+    });
+
   });
 
   describe('ssl', function() {