connect method

@override Future<MqttConnectionStatus?> connect(String server, int port)

Connect

Implementation

@override
Future<MqttConnectionStatus?> connect(String server, int port) {
  final completer = Completer<MqttConnectionStatus?>();
  MqttLogger.log('MqttServerWs2Connection::connect - entered');
  Uri uri;
  try {
    uri = Uri.parse(server);
  } on Exception catch (_, stack) {
    final message =
        'MqttWsConnection::The URI supplied for the WS2 connection '
        'is not valid - $server';
    Error.throwWithStackTrace(MqttNoConnectionException(message), stack);
  }
  if (uri.scheme != 'wss') {
    final message =
        'MqttWsConnection::The URI supplied for the WS2 has an '
        'incorrect scheme - $server';
    throw MqttNoConnectionException(message);
  }
  uri = uri.replace(port: port);
  final uriString = uri.toString();
  MqttLogger.log(
    'MqttServerWs2Connection:: WS URL is $uriString, protocols are $protocols',
  );

  try {
    SecureSocket.connect(
      uri.host,
      uri.port,
      context: context,
      onBadCertificate: onBadCertificate,
    ).then((Socket socket) {
      MqttLogger.log('MqttServerWs2Connection::connect - securing socket');
      _performWSHandshake(socket, uri)
          .then((bool b) {
            client = WebSocket.fromUpgradedSocket(
              _DetachedSocket(
                socket,
                _subscription as StreamSubscription<Uint8List>?,
              ),
              serverSide: false,
            );
            MqttLogger.log(
              'MqttServerWs2Connection::connect - start listening',
            );
            _startListening();
            completer.complete();
          })
          .catchError((dynamic e) {
            onError(e);
            completer.completeError(e);
          });
    });
  } on SocketException catch (e, stack) {
    final message =
        'MqttServerWs2Connection::The connection to the message broker '
        '{$server}:{$port} could not be made. Error is ${e.toString()}';
    completer.completeError(e);
    Error.throwWithStackTrace(MqttNoConnectionException(message), stack);
  } on HandshakeException catch (e, stack) {
    final message =
        'MqttServerWs2Connection::Handshake exception to the message broker '
        '{$server}:{$port}. Error is ${e.toString()}';
    completer.completeError(e);
    Error.throwWithStackTrace(MqttNoConnectionException(message), stack);
  } on TlsException catch (e, stack) {
    final message =
        'MqttServerWs2Connection::TLS exception raised on secure connection. '
        'Error is ${e.toString()}';
    Error.throwWithStackTrace(MqttNoConnectionException(message), stack);
  }
  return completer.future;
}