Initial web socket server implementation

runtime/bin/websocket.dart

+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+/**
+ * The web socket protocol is implemented by a HTTP server handler
+ * which can be instantiated like this:
+ *
+ * WebSocketHandler wsHandler = new WebSocketHandler();
+ *
+ * and then its onRequest method can be assigned to the HTTP server, e.g.
+ *
+ * server.defaultHandler = wsHandler.onRequest;
+ *
+ * or
+ *
+ * server.addRequestHandler((req) => reg.path == "/ws", wsHandler.onRequest);
+ *
+ */
+interface WebSocketHandler default _WebSocketHandler {
+  WebSocketHandler();
+
+  /**
+   * Request handler to be registered with the HTTP server.
+   */
+  void onRequest(HttpRequest request, HttpResponse response);
+
+  /**
+   * Sets the callback to be called when a new web socket connection
+   * has been established.
+   */
+  void set onOpen(callback(WebSocketConnection connection));
+}
+
+
+/**
+ * Web socket connection.
+ */
+interface WebSocketConnection {
+  /**
+   * Sets the callback to be called when a message have been
+   * received. The type on [message] is either [:String:] or
+   * [:List<int>:] depending on whether it is a text or binary
+   * message. If the message is empty [message] will be [:null:].
+   */
+  void set onMessage(void callback(message));
+
+  /**
+   * Sets the callback to be called when the web socket connection is
+   * closed.
+   */
+  void set onClosed(void callback(int status, String reason));
+
+  /**
+   * Sets the callback to be called when the web socket connection
+   * encountered an error.
+   */
+  void set onError(void callback(e));
+
+  /**
+   * Sends a message. The [message] must be a [:String:] a
+   * [:List<int>:] or [:null:].
+   */
+  send(Object message);
+
+  /**
+   * Close the web socket connection. The default value for [status]
+   * and [reason] are [:null:].
+   */
+  close([int status, String reason]);
+}
+
+
+class WebSocketException implements Exception {
+  const WebSocketException([String this.message = ""]);
+  String toString() => "WebSocketException: $message";
+  final String message;
+}