connect method

Future<bool> connect()

Implementation

Future<bool> connect() async {
  var uri = Uri.parse(url);
  var secretKey = secKey();
  var socket = await Socket.connect(uri.host, uri.port);
  _channel = WebSocketChannel(socket, mask: true);
  socket.listen((event) {
    if (_channel.handshaked) {
      var frame = WebSocketFrame.create(event);
      switch (frame.opcode) {
        case OpCode.text:
          provider.onText(String.fromCharCodes(frame.payload), _channel);
          break;
        case OpCode.binary:
          provider.onMessage(frame.payload, _channel);
          break;
        case OpCode.close:
          provider.onClosed(
              CloseCodeExtension.parse(frame.payload.uint16), _channel);
          break;
        case OpCode.ping:
          provider.onPing(frame.payload, _channel);
          break;
        case OpCode.pong:
          provider.onPong(frame.payload, _channel);
          break;
        case OpCode.reserved:
          break;
      }
    } else {
      var secAcceptKey = String.fromCharCodes(event.toList())
          .split('\r\n')
          .firstWhere(
              (element) => element.startsWith('Sec-WebSocket-Accept: '),
              orElse: () => '')
          .split(': ')
          .last;
      var expectKey = convert.base64.encoder.convert(sha1
          .convert(
              (secretKey + '258EAFA5-E914-47DA-95CA-C5AB0DC85B11').codeUnits)
          .bytes);
      if (secAcceptKey == expectKey) {
        _channel.handshaked = true;
        provider.onConnected(_channel);
      } else {
        provider.onClosed(CloseCode.protocolError, _channel);
      }
    }
  }, onError: (error) {
    provider.onClosed(CloseCode.error, _channel);
  }, onDone: () {
    socket.destroy();
    provider.onClosed(CloseCode.normal, _channel);
  });

  List<String> h = [];
  h.add('GET ${url} HTTP/1.1');
  h.add('Host: ${uri.host}:${uri.port}');
  h.add('Upgrade: websocket');
  h.add('Connection: Upgrade');
  h.add('Sec-WebSocket-Key: $secretKey');
  h.add('Sec-WebSocket-Version: 13');
  h.add(
      'Sec-WebSocket-Extensions: permessage-deflate; client_max_window_bits');

  headers?.forEach((key, value) {
    h.add('$key: $value');
  });
  var head = h.join("\r\n") + "\r\n";
  socket.write(head);
  return true;
}