connect method

Implementation

@override
Future<bool> connect() async {
  Log().debug('MQTT:: Connecting to $url on port ${client.port}');

  /// Create a connection message to use or use the default one. The default one sets the
  /// client identifier, any supplied username/password, the default keepalive interval(60s)
  /// and clean session, an example of a specific one below.
  final connMess = MqttConnectMessage();
  connMess.withClientIdentifier(identifier);
  connMess.startClean();
  if (username != null) connMess.authenticateAs(username, password);

  client.connectionMessage = connMess;
  client.keepAlivePeriod = keepalive;

  /// Connect the client, any errors here are communicated by raising of the appropriate exception. Note
  /// in some circumstances the source will just disconnect us, see the spec about this, we however will
  /// never send malformed messages.
  try {
    await client.connect();
  } on Exception catch (e) {
    Log().debug(
        'MQTT:: Error Connecting to $url on port ${client.port}. Status is $e');
    client.disconnect();
  }

  if (client.connectionStatus!.state == MqttConnectionState.connected) {
    Log().debug('MQTT:: Client Connected');
  } else {
    Log().debug(
        'MQTT:: Error Connecting to $url on port ${client.port}. Status is ${client.connectionStatus}');
    client.disconnect();
    return false;
  }

  return true;
}