emitWithAck method

Implementation

void emitWithAck(String event, dynamic data,
    {Function? ack, bool binary = false}) {
  if (events.contains(event)) {
    super.emit(event, data);
  } else {
    var sendData = <dynamic>[event];
    if (data is ByteBuffer || data is List<int>) {
      sendData.add(data);
    } else if (data is Iterable) {
      sendData.addAll(data);
    } else if (data != null) {
      sendData.add(data);
    }

    var packet = {
      'type': EVENT,
      'data': sendData,
      'options': {'compress': flags.isNotEmpty == true && flags['compress']}
    };

    // event ack callback
    if (ack != null) {
      _logger.fine('emitting packet with ack id $ids');
      acks['$ids'] = ack;
      packet['id'] = '${ids++}';
    }
    final isTransportWritable = io.engine != null &&
        io.engine!.transport != null &&
        io.engine!.transport!.writable == true;

    final discardPacket =
        flags['volatile'] != null && (!isTransportWritable || !connected);
    if (discardPacket) {
      _logger
          .fine('discard packet as the transport is not currently writable');
    } else if (connected) {
      this.packet(packet);
    } else {
      sendBuffer.add(packet);
    }
    flags = {};
  }
}