即使客户端关闭，Amqp、rabbit mq 和 socket.io 也会重新连接到队列

Question

我正在使用 rabbitMQ 和 socket.io 编写浏览器通知。除了一种情况，我的配置工作正常。

当我使用用户登录我的系统时，它会创建一个通知-UID-userid 队列（现在 queueName 由查询 oaraeter 发送，我将尽快实施更复杂的方法解决问题）

如果我在另一个浏览器上使用另一个用户登录，它会创建另一个队列通知-UID-seconduserid。

如果我注销其中一个用户，队列将消失（因为它不持久）。

问题是，当我在另一个会话上刷新或加载另一个页面时，即使未发送参数队列名，它也会重新创建第二个队列。

server.js

var amqp = require('amqp');
var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);

var rabbitMqConnection = null;
var _queue = null;
var _consumerTag = null;


io.use(function (socket, next) {
    var handshakeData = socket.handshake;
    // Here i will implement token verification
    console.log(socket.handshake.query.queueName);
    next();
});


// Gets the connection event form client
io.sockets.on('connection', function (socket) {

    var queueName = socket.handshake.query.queueName;

    console.log("Socket Connected");

    // Connects to rabbiMq
    rabbitMqConnection = amqp.createConnection({host: 'localhost', reconnect: false});

    // Update our stored tag when it changes
    rabbitMqConnection.on('tag.change', function (event) {
        if (_consumerTag === event.oldConsumerTag) {
            _consumerTag = event.consumerTag;
            // Consider unsubscribing from the old tag just in case it lingers
            _queue.unsubscribe(event.oldConsumerTag);
        }
    });

    // Listen for ready event
    rabbitMqConnection.on('ready', function () {
        console.log('Connected to rabbitMQ');

        // Listen to the queue
        rabbitMqConnection.queue(queueName, {
                closeChannelOnUnsubscribe: true,
                durable: false,
                autoClose: true
            },
            function (queue) {
                console.log('Connected to ' + queueName);
                _queue = queue;

                // Bind to the exchange
                queue.bind('users.direct', queueName);

                queue.subscribe({ack: false, prefetchCount: 1}, function (message, headers, deliveryInfo, ack) {
                    console.log("Received a message from route " + deliveryInfo.routingKey);
                    socket.emit('notification', message);
                    //ack.acknowledge();
                }).addCallback(function (res) {
                    // Hold on to the consumer tag so we can unsubscribe later
                    _consumerTag = res.consumerTag;
                });
            });
    });


    // Listen for disconnection
    socket.on('disconnect', function () {
        _queue.unsubscribe(_consumerTag);
        rabbitMqConnection.disconnect();
        console.log("Socket Disconnected");
    });

});

http.listen(8080);

client.js

var io = require('socket.io-client');

$(document).ready(function () {

    var socket = io('http://myserver.it:8080/', {
         query:  { queueName: 'notification-UID-' + UID},
        'sync disconnect on unload': true,
        });

    socket.on('notification', function (data) {
        console.log(data);
    });
})

有什么想法吗？

Answer 1

所以我解决了我的问题，这是一个变量范围的问题，把事情搞砸了。 让我解释一下我在做什么，也许它可能对某人有用。

基本上我正在尝试创建一个浏览器通知系统，这意味着我的应用程序（生产者端）向交换器发布一个通知对象，其中包含一些信息，例如主题、链接和消息。

交换是一个 fanout (users.notification.fanout)，有两个绑定交换：users.direct（直接类型）和users.notification.store（扇出类型）。

当生产者发布通知时，它会使用路由键“notification-UID-userid”发送到 users.notification.fanout（其中 userid 是真实的用户 ID。

通知对象同时发送到 users.direct 和 users.notification.store 最后一个有一个消费者将通知写入数据库，以防用户未登录，第一个消费者将通知发布到浏览器。

那么浏览器消费者是如何工作的呢？

我使用了socket.io、node server和amqplib的经典组合。

每次用户登录时，socket.io 都会创建一个队列，其中包含名称和路由密钥 notification-UID-userid，并将其绑定到 users.direct 交换。

与此同时，我已将 https 添加到我的服务器，因此与第一个版本相比有所改变。

你可以阅读 cmets 来了解它的作用。

所以我的 server.js 是

var amqp = require('amqp');
var fs = require('fs');
var app = require('express')();
// Https server, certificates and private key added
var https = require('https').Server({
    key: fs.readFileSync('/home/www/site/privkey.pem'),
    cert: fs.readFileSync('/home/www/site/fullchain.pem')},app);
var io = require('socket.io')(https);

// Used to verify if token is valid
// If not it will discard connection
io.use(function (socket, next) {
    var handshakeData = socket.handshake;
    // Here i will implement token verification
    console.log("Check this token: " + handshakeData.query.token);
    next();
});
// Gets the connection event from client
io.sockets.on('connection', function (socket) {
    // Connection log
    console.log("Socket Connected with ID: " + socket.id);
    // THIS WAS THE PROBLEM
    // Local variables for connections
    // Former i've put these variables outside the connection so at 
    // every client they were "overridden". 
    // RabbitMq Connection (Just for current client)
    var _rabbitMqConnection = null;
    // Queue (just for current client)
    var _queue = null;
    // Consumer tag (just for current client)
    var _consumerTag = null;
    // Queue name and routing key for current user
    var queueName = socket.handshake.query.queueName;
    // Connects to rabbiMq with default data to localhost guest guest
    _rabbitMqConnection = amqp.createConnection();
    // Connection ready
    _rabbitMqConnection.on('ready', function () {
        // Connection log
        console.log('#' + socket.id + ' - Connected to RabbitMQ');
        // Creates the queue (default is transient and autodelete)
        // https://www.npmjs.com/package/amqp#connectionqueuename-options-opencallback
        _rabbitMqConnection.queue(queueName, function (queue) {
            // Connection log
            console.log('#' + socket.id + ' - Connected to ' + queue.name + ' queue');
            // Stores local queue
            _queue = queue;
            // Bind to the exchange (default)
            queue.bind('users.direct', queueName, function () {
                // Binding log
                console.log('#' + socket.id + ' - Binded to users.direct exchange');
                // Consumer definition
                queue.subscribe({ack: false}, function (message, headers, deliveryInfo, messageObject) {
                    // Message log
                    console.log('#' + socket.id + ' - Received a message from route ' + deliveryInfo.routingKey);
                    // Emit the message to the client
                    socket.emit('notification', message);
                }).addCallback(function (res) {
                    // Hold on to the consumer tag so we can unsubscribe later
                    _consumerTag = res.consumerTag;
                    // Consumer tag log
                    console.log('#' + socket.id + ' - Consumer ' + _consumerTag + ' created');
                })
            });

        });
    });
    // Update our stored tag when it changes
    _rabbitMqConnection.on('tag.change', function (event) {
        if (_consumerTag === event.oldConsumerTag) {
            _consumerTag = event.consumerTag;
            // Unsubscribe from the old tag just in case it lingers
            _queue.unsubscribe(event.oldConsumerTag);
        }
    });
    // Listen for disconnection
    socket.on('disconnect', function () {
        _queue.unsubscribe(_consumerTag);
        _rabbitMqConnection.disconnect();
        console.log('#' + socket.id + ' - Socket Disconnected');
    });
});

https.listen(8080);

然后是我的 client.js

var io = require('socket.io-client');

$(document).ready(function () {

    var socket = io('https://myserver.com:8080/', {
        secure: true, // for ssl connections
        query:  { queueName: 'notification-UID-' + UID, token: JWTToken}, // params sent to server, JWTToken for authentication
        'sync disconnect on unload': true // Every time the client unload, socket disconnects
    });

    socket.on('notification', function (data) {
        // Do what you want with your data
        console.log(data);
    });
})