Allow Observatory to run as a hosted web service

runtime/bin/vmservice/client/lib/src/app/target_manager.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.
+
+part of app;
+
+class ChromiumTargetLister {
+  /// Fetch the list of chromium [NetworkVMTargets].
+  static Future<List<WebSocketVMTarget>> fetch(String networkAddress) {
+    if (networkAddress == null) {
+      return new Future.error(null);
+    }
+    var encoded = Uri.encodeComponent(networkAddress);
+    var url = '/crdptargets/$encoded';
+    return HttpRequest.getString(url).then((String responseText) {
+      var list = JSON.decode(responseText);
+      if (list == null) {
+        return list;
+      }
+      for (var i = 0; i < list.length; i++) {
+        list[i] = new WebSocketVMTarget.fromMap(list[i]);
+      }
+      return list;
+    }).catchError((e) {
+      // An error occured while getting the list of Chrome targets.
+      // We eagerly request the list of targets, meaning this error can occur
+      // regularly. By catching it and dropping it, we avoid spamming errors
+      // on the console.
+    });
+  }
+}
+
+class TargetManager extends Observable {
+  static const _historyKey = 'history';
+  final SettingsGroup _settings = new SettingsGroup('targetManager');
+  final List history = new ObservableList();
+  WebSocketVMTarget defaultTarget;
+
+  String _networkAddressOfDefaultTarget() {
+    if (Utils.runningInJavaScript()) {
+      // We are running as JavaScript, use the same host that Observatory has
+      // been loaded from.
+      return 'ws://${window.location.host}/ws';
+    } else {
+      // Otherwise, assume we are running from Dart Editor and want to connect
+      // to the default host.
+      return 'ws://localhost:8181/ws';
+    }
+  }
+  TargetManager() {
+    _restore();
+    // Add a default standalone VM target.
+    defaultTarget = findOrMake(_networkAddressOfDefaultTarget());
+    assert(defaultTarget != null);
+    add(defaultTarget);
+  }
+
+  void clearHistory() {
+    history.clear();
+    _store();
+  }
+
+  WebSocketVMTarget findOrMake(String networkAddress) {
+    var target;
+    target = _find(networkAddress);
+    if (target != null) {
+      return target;
+    }
+    target = new WebSocketVMTarget(networkAddress);
+    return target;
+  }
+
+  /// Find by networkAddress.
+  WebSocketVMTarget _find(String networkAddress) {
+    var r;
+    history.forEach((item) {
+      if ((item.networkAddress == networkAddress) && (item.chrome == false)) {
+        r = item;
+      }
+    });
+    return r;
+  }
+
+  void add(WebSocketVMTarget item) {
+    if (item.chrome) {
+      // We don't store chrome tabs.
+      return;
+    }
+    if (history.contains(item)) {
+      return;
+    }
+    // Not inserting duplicates.
+    assert(_find(item.networkAddress) == null);
+    history.add(item);
+    _sort();
+    _store();
+  }
+
+  void remove(WebSocketVMTarget target) {
+    history.remove(target);
+    _sort();
+    _store();
+  }
+
+  void _sort() {
+    this.history.sort((WebSocketVMTarget a, WebSocketVMTarget b) {
+      return b.lastConnectionTime.compareTo(a.lastConnectionTime);
+    });
+  }
+
+  /// After making a change, update settings.
+  void _store() {
+    _sort();
+    _settings.set(_historyKey,  history);
+  }
+
+  /// Read settings from data store.
+  void _restore() {
+    this.history.clear();
+    var loaded = _settings.get(_historyKey);
+    if (loaded == null) {
+      return;
+    }
+    for (var i = 0; i < loaded.length; i++) {
+      loaded[i] = new WebSocketVMTarget.fromMap(loaded[i]);
+    }
+    this.history.addAll(loaded);
+    _sort();
+  }
+}