断开的插座中的孤立消费者

Question

堆栈使用Socket.io，redis和RabbitMQ作为消息传递平台。 问题

连接套接字后，将创建到Rabbit mq的队列，在断开连接事件中存在使用者取消逻辑。问题在于互联网设置有问题，然后在执行队列创建的回调之后首先触发了断开连接，因此创建了孤立队列。

服务器代码

io.on('connection', async function(socket){ 
      socket.on('initializationAcknowledged', function(){
           // Creating a queue on rabbit MQ in auto delete setting 
           // That is the queue will exists till a consumer is present 
           // We cancel the consumer in on disconnect event
           rabbitMQ.assertQueue('', {autoDelete: true, expires: 6000}, function(err, q) {
                if (err) {
                    console.log('Error while asserting the consumer queue.');
                };

                // Bind the queue  
                consumer.bindQueue(q.queue, 'some exchange', socket.userID);

                // Creating the consumer to consume on the created queue
                consumer.consume(q.queue, function(msg) {

                }, {noAck: true}, function(err, obj) {
                    if (err) {
                        console.log('There was an errow while assigning a consumer ');
                    }
                    // Setting the consumer tag on the socket to cancel consumer.
                    socket.consumerTag = obj.consumerTag;
                });
            });
      })
      // This is to make sure we have initialized and a stable internet connection
      socket.emit('initialization')

      socket.on('disconnect', function(){
            // It fires the disconnet event before and finds the consumerTag as undefined hence does not cancel.
            if (socket.consumerTag != undefined) {
                consumer.cancel(socket.consumerTag, function(err, ok) {
                    if (err) {
                        console.log('Error while cancelling the consumer:', err);
                    }
                    if (ok) {
                        console.log('Consumer cancelled successfully', ok);
                    }
                });
            }
      });
})

客户代码

const socket = io.connect("some url")
socket.on('initialization', function(data){
       // This is to make sure we have a stable internet connection
        socket.emit('initializationAcknowledged');
}

Answer 1

为什么不使用dns.lookup（url，callback）检查Internet连接？ 如果回调返回true，则仅使用断开连接方法。