Split channels library.

pkg/analysis_server/lib/src/channel/web_socket_channel.dart

+// Copyright (c) 2014, 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.
+
+library channel.web_socket;
+
+import 'dart:async';
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:analysis_server/src/protocol.dart';
+import 'package:analysis_server/src/channel/channel.dart';
+
+
+/**
+ * Instances of the class [WebSocketClientChannel] implement a
+ * [ClientCommunicationChannel] that uses a [WebSocket] to communicate with
+ * servers.
+ */
+class WebSocketClientChannel implements ClientCommunicationChannel {
+  /**
+   * The socket being wrapped.
+   */
+  final WebSocket socket;
+
+  @override
+  Stream<Response> responseStream;
+
+  @override
+  Stream<Notification> notificationStream;
+
+  /**
+   * Initialize a new [WebSocket] wrapper for the given [socket].
+   */
+  WebSocketClientChannel(this.socket) {
+    Stream jsonStream = socket
+        .where((data) => data is String)
+        .transform(new JsonStreamDecoder())
+        .where((json) => json is Map)
+        .asBroadcastStream();
+    responseStream = jsonStream
+        .where((json) => json[Notification.EVENT] == null)
+        .transform(new ResponseConverter())
+        .asBroadcastStream();
+    notificationStream = jsonStream
+        .where((json) => json[Notification.EVENT] != null)
+        .transform(new NotificationConverter())
+        .asBroadcastStream();
+  }
+
+  @override
+  Future<Response> sendRequest(Request request) {
+    String id = request.id;
+    socket.add(JSON.encode(request.toJson()));
+    return responseStream.firstWhere((Response response) => response.id == id);
+  }
+
+  @override
+  Future close() {
+    return socket.close();
+  }
+}
+
+/**
+ * Instances of the class [WebSocketServerChannel] implement a
+ * [ServerCommunicationChannel] that uses a [WebSocket] to communicate with
+ * clients.
+ */
+class WebSocketServerChannel implements ServerCommunicationChannel {
+  /**
+   * The socket being wrapped.
+   */
+  final WebSocket socket;
+
+  /**
+   * Initialize a newly create [WebSocket] wrapper to wrap the given [socket].
+   */
+  WebSocketServerChannel(this.socket);
+
+  @override
+  void listen(void onRequest(Request request), {void onError(), void onDone()}) {
+    socket.listen((data) => readRequest(data, onRequest), onError: onError,
+        onDone: onDone);
+  }
+
+  @override
+  void sendNotification(Notification notification) {
+    socket.add(JSON.encode(notification.toJson()));
+  }
+
+  @override
+  void sendResponse(Response response) {
+    socket.add(JSON.encode(response.toJson()));
+  }
+
+  /**
+   * Read a request from the given [data] and use the given function to handle
+   * the request.
+   */
+  void readRequest(Object data, void onRequest(Request request)) {
+    if (data is String) {
+      // Parse the string as a JSON descriptor and process the resulting
+      // structure as a request.
+      Request request = new Request.fromString(data);
+      if (request == null) {
+        sendResponse(new Response.invalidRequestFormat());
+        return;
+      }
+      onRequest(request);
+    } else if (data is List<int>) {
+      // TODO(brianwilkerson) Implement a more efficient protocol.
+      sendResponse(new Response.invalidRequestFormat());
+    } else {
+      sendResponse(new Response.invalidRequestFormat());
+    }
+  }
+
+  @override
+  void close() {
+    socket.close(WebSocketStatus.NORMAL_CLOSURE);
+  }
+}