message: check if targetClient is undefined
diff: @@ -91,8 +91,10 @@ class Client extends events.EventEmitter {
  }
  if (this.room.p2p) {
  const targetClient = this.room.getClientById(message.peerSocket);
  + if (targetClient) {
  targetClient.sendMessage('signaling_message_peer',
  {streamId: message.streamId, peerSocket: this.id, msg: message.msg});
  + }
  } else {
  const isControlMessage = message.msg.type === 'control';
  if (!isControlMessage ||
  