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

node-amqplib rabbitmq socket.io javascript

Jack Skeletron · 技术社区 · 8 年前

当我用用户登录到我的系统时,它会创建一个通知UID- 用户ID queue(目前queueName是由query oaraeter发送的,我将在解决问题后立即实现更详细的方法)

第二用户ID .

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,当我在另一个会话中刷新或加载另一个页面时,即使参数queuename未发送,它也会重新创建第二个队列。

服务器.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);

客户端.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);
    });
})

知道吗?

1 回复 | 直到 8 年前

Jack Skeletron 8 年前

所以我解决了我的问题,这是一个可变范围的问题,把事情搞砸了。让我解释一下我在做什么,也许对某人有用。

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将包含一些信息(如主题、链接和消息)的通知对象发布到exchange(生产者端)。

交易所是 扇形分叉 ( 用户.notification.fanout 用户.direct 用户.notification.store (扇出型)。

用户ID

通知对象同时指向users.direct和users.notification.store 最后一个用户将通知写入数据库以防用户未登录,第一个用户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。

用户ID 并将其绑定到用户。直接交换。

同时,我在我的服务器上添加了https,所以与第一个版本相比有些变化。

所以我的 服务器.js

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);

那么我的 客户端.js

var io=需要('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);
    });
})