code: function () {
          for (let i = this.clients.length - 1; i > -1; --i) {
              if (this.clients[i].connect.state !== 'open') {
                  this.clients.splice(i, 1);
              }
          }
      }
docs: const STATE_OPEN = 'open'; // Connected, fully-open, ready to send and receive frames
  const STATE_PEER_REQUESTED_CLOSE = 'peer_requested_close';// Received a close frame from the remote peer
  const STATE_ENDING = 'ending';// Sent close frame to remote peer.  No further data can be sent.
  const STATE_CLOSED = 'closed';// Connection is fully closed.  No further data can be sent or received.
  检查 WebSocket connect双供通道是否有效，失效通道将会被踢出连接池