Future _startSseClient()

in dwds/debug_extension/web/background.dart [331:420]
81 lines of code
13 McCabe index (conditional complexity)

Future<void> _startSseClient(
  Uri uri,
  String appId,
  String instanceId,
  int contextId,
  Tab currentTab,
  String dwdsVersion,
) async {
  if (Version.parse(dwdsVersion ?? '0.0.0') >= Version.parse('9.1.0')) {
    var authUri = uri.replace(path: authenticationPath);
    if (authUri.scheme == 'ws') authUri = authUri.replace(scheme: 'http');
    if (authUri.scheme == 'wss') authUri = authUri.replace(scheme: 'https');
    var authUrl = authUri.toString();
    try {
      var response = await HttpRequest.request(authUrl,
          method: 'GET', withCredentials: true);
      if (!response.responseText
          .contains('Dart Debug Authentication Success!')) {
        throw Exception('Not authenticated.');
      }
    } catch (_) {
      if (window.confirm(
          'Authentication required.\n\nClick OK to authenticate then try again.')) {
        // TODO(grouma) - see if we can get a callback on a successful auth
        // and automatically reinitiate the dev workflow.
        window.open(authUrl, 'Dart DevTools Authentication');
        detach(Debuggee(tabId: currentTab.id), allowInterop(() {}));
      }
      return;
    }
  }

  // Specifies whether the debugger is attached.
  //
  // A debugger is detached if it is closed by user or the target is closed.
  var client = uri.isScheme('ws') || uri.isScheme('wss')
      ? WebSocketClient(WebSocketChannel.connect(uri))
      : SseSocketClient(SseClient(uri.toString()));
  _debugSessions.add(DebugSession(client, currentTab.id));
  print('Connected to DWDS version $dwdsVersion with appId=$appId');
  client.stream.listen((data) {
    var message = serializers.deserialize(jsonDecode(data));
    if (message is ExtensionRequest) {
      var params =
          BuiltMap<String, Object>(json.decode(message.commandParams)).toMap();
      sendCommand(Debuggee(tabId: currentTab.id), message.command,
          js_util.jsify(params), allowInterop(([e]) {
        // No arguments indicate that an error occurred.
        if (e == null) {
          client.sink
              .add(jsonEncode(serializers.serialize(ExtensionResponse((b) => b
                ..id = message.id
                ..success = false
                ..result = stringify(lastError)))));
        } else {
          client.sink
              .add(jsonEncode(serializers.serialize(ExtensionResponse((b) => b
                ..id = message.id
                ..success = true
                ..result = stringify(e)))));
        }
      }));
    } else if (message is ExtensionEvent) {
      if (message.method == 'dwds.encodedUri') {
        sendMessageToExtensions(Request(
            name: 'dwds.encodedUri',
            tabId: currentTab.id,
            options: message.params));
        _tabIdToEncodedUri[currentTab.id] = message.params;
      }
    }
  }, onDone: () {
    _tabIdToEncodedUri.remove(currentTab.id);
    client.close();
    return;
  }, onError: (_) {
    _tabIdToEncodedUri.remove(currentTab.id);
    alert('Lost app connection.');
    client.close();
  }, cancelOnError: true);

  client.sink.add(jsonEncode(serializers.serialize(DevToolsRequest((b) => b
    ..appId = appId
    ..instanceId = instanceId
    ..contextId = contextId
    ..tabUrl = currentTab.url))));

  sendCommand(Debuggee(tabId: currentTab.id), 'Runtime.enable', EmptyParam(),
      allowInterop((e) {}));
}