Enable using the service library from dart:io applications.

runtime/bin/vmservice/client/lib/service_common.dart

Index: runtime/bin/vmservice/client/lib/service_common.dart
===================================================================
--- runtime/bin/vmservice/client/lib/service_common.dart	(revision 38598)
+++ runtime/bin/vmservice/client/lib/service_common.dart	(working copy)
@@ -2,11 +2,10 @@
 // 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 service_html;
+library service_common;
 
 import 'dart:async';
 import 'dart:convert';
-import 'dart:html';
 
 import 'package:logging/logging.dart';
 import 'package:observatory/service.dart';
@@ -60,10 +59,23 @@
       : completer = new Completer<String>();
 }
 
-/// The [WebSocketVM] communicates with a Dart VM over WebSocket. The Dart VM
-/// can be embedded in Chromium or standalone. In the case of Chromium, we
-/// make the service requests via the Chrome Remote Debugging Protocol.
-class WebSocketVM extends VM {
+/// Minimal common interface for 'WebSocket' in [dart:io] and [dart:html].
+abstract class CommonWebSocket {
+  void connect(String address,
+               void onOpen(),
+               void onMessage(dynamic data),
+               void onError(),
+               void onClose());
+  bool get isOpen;
+  void send(dynamic data);
+  void close();
+}
+
+/// A [CommonWebSocketVM] communicates with a Dart VM over a CommonWebSocket.
+/// The Dart VM can be embedded in Chromium or standalone. In the case of
+/// Chromium, we make the service requests via the Chrome Remote Debugging
+/// Protocol.
+abstract class CommonWebSocketVM extends VM {
   final Completer _connected = new Completer();
   final Completer _disconnected = new Completer();
   final WebSocketVMTarget target;
@@ -72,9 +84,11 @@
   final Map<String, _WebSocketRequest> _pendingRequests =
       new Map<String, _WebSocketRequest>();
   int _requestSerial = 0;
-  WebSocket _webSocket;
+  bool _hasInitiatedConnect = false;
 
-  WebSocketVM(this.target) {
+  CommonWebSocket _webSocket;
+
+  CommonWebSocketVM(this.target, this._webSocket) {
     assert(target != null);
   }
 
@@ -94,7 +108,7 @@
   Future get onDisconnect => _disconnected.future;
 
   void disconnect() {
-    if (_webSocket != null) {
+    if (_hasInitiatedConnect) {
       _webSocket.close();
     }
     _cancelAllRequests();
@@ -102,24 +116,21 @@
   }
 
   Future<String> getString(String id) {
-    if (_webSocket == null) {
-      // Create a WebSocket.
-      _webSocket = new WebSocket(target.networkAddress);
-      _webSocket.onClose.listen(_onClose);
-      _webSocket.onError.listen(_onError);
-      _webSocket.onOpen.listen(_onOpen);
-      _webSocket.onMessage.listen(_onMessage);
+    if (!_hasInitiatedConnect) {
+      _hasInitiatedConnect = true;
+      _webSocket.connect(
+          target.networkAddress, _onOpen, _onMessage, _onError, _onClose);
     }
     return _makeRequest(id);
   }
 
   /// Add a request for [id] to pending requests.
   Future<String> _makeRequest(String id) {
-    assert(_webSocket != null);
+    assert(_hasInitiatedConnect);
     // Create request.
     String serial = (_requestSerial++).toString();
     var request = new _WebSocketRequest(id);
-    if (_webSocket.readyState == WebSocket.OPEN) {
+    if (_webSocket.isOpen) {
       // Already connected, send request immediately.
       _sendRequest(serial, request);
     } else {
@@ -129,27 +140,28 @@
     return request.completer.future;
   }
 
-  void _onClose(CloseEvent event) {
+  void _onClose() {
     _cancelAllRequests();
     _notifyDisconnect();
   }
 
   // WebSocket error event handler.
-  void _onError(Event) {
+  void _onError() {
     _cancelAllRequests();
     _notifyDisconnect();
   }
 
   // WebSocket open event handler.
-  void _onOpen(Event) {
+  void _onOpen() {
     target.lastConnectionTime = new DateTime.now().millisecondsSinceEpoch;
     _sendAllDelayedRequests();
     _notifyConnect();
   }
 
   // WebSocket message event handler.
-  void _onMessage(MessageEvent event) {
-    var map = JSON.decode(event.data);
+  void _onMessage(dynamic data) {
+    assert(data is String);  // We don't handle binary data, yet.
+    var map = JSON.decode(data);
     if (map == null) {
       Logger.root.severe('WebSocketVM got empty message');
       return;
@@ -214,7 +226,7 @@
 
   /// Send all delayed requests.
   void _sendAllDelayedRequests() {
-    assert(_webSocket != null);
+    assert(_webSocket.isOpen);
     if (_delayedRequests.length == 0) {
       return;
     }
@@ -227,7 +239,7 @@
 
   /// Send the request over WebSocket.
   void _sendRequest(String serial, _WebSocketRequest request) {
-    assert (_webSocket.readyState == WebSocket.OPEN);
+    assert (_webSocket.isOpen);
     if (!request.id.endsWith('/profile/tag')) {
       Logger.root.info('GET ${request.id} from ${target.networkAddress}');
     }
@@ -252,46 +264,3 @@
     _webSocket.send(message);
   }
 }
-
-// A VM that communicates with the service via posting messages from DevTools.
-class PostMessageVM extends VM {
-  final Completer _connected = new Completer();
-  final Completer _disconnected = new Completer();
-  void disconnect() { /* nope */ }
-  Future get onConnect => _connected.future;
-  Future get onDisconnect => _disconnected.future;
-  final Map<String, Completer> _pendingRequests =
-      new Map<String, Completer>();
-  int _requestSerial = 0;
-
-  PostMessageVM() : super() {
-    window.onMessage.listen(_messageHandler);
-    _connected.complete(this);
-  }
-
-  void _messageHandler(msg) {
-    var id = msg.data['id'];
-    var name = msg.data['name'];
-    var data = msg.data['data'];
-    if (name != 'observatoryData') {
-      return;
-    }
-    var completer = _pendingRequests[id];
-    assert(completer != null);
-    _pendingRequests.remove(id);
-    completer.complete(data);
-  }
-
-  Future<String> getString(String path) {
-    var idString = '$_requestSerial';
-    Map message = {};
-    message['id'] = idString;
-    message['method'] = 'observatoryQuery';
-    message['query'] = '$path';
-    _requestSerial++;
-    var completer = new Completer();
-    _pendingRequests[idString] = completer;
-    window.parent.postMessage(JSON.encode(message), '*');
-    return completer.future;
-  }
-}