Question

我在这里度过了一段时间。我已经阅读了大量文档和其他人对同一主题的问题，但无法找到如何阻止这种情况发生的答案。我故意关闭redis服务器，以确保应用程序在生产过程中不会完全核，但我做的任何事情似乎都不会阻止它发生。这是我的代码现在的一个非常简单的例子......

var cluster = require('cluster');
var express = require('express');
var http = require('http');
var redis = require('redis');
var redisAdapter = require('socket.io-redis');
var sticky = require('sticky-session');
var port = process.env.PORT || 3333;
var workers = 3;
var app = express();
var server = http.createServer(app);
var io = require('socket.io')(server);

if(!sticky.listen(server, 3333, {workers: workers})) {
    server.once('listening', () => {
        console.log('server started on port ' + port);
        process.on('exit', () => {
            io.emit('error', {errorType: 'SERVER_SHUTDOWN'});
        });
        process.on('uncaughtException', (err) => {
            console.log('uncaught exception occurred');
            console.log(err);
        });
    });
} else {
    addRedisAdapter(io);
    addIOEventHandler(io);
}

function addRedisAdapter(io) {
    var redisUrl = process.env.REDISTOGO_URL || 'redis://127.0.0.1:6379';
    var redisOptions = require('parse-redis-url')(redis).parse(redisUrl);
    var pub = redis.createClient(redisOptions.port, redisOptions.host, { returnBuffers: true});
    var sub = redis.createClient(redisOptions.port, redisOptions.host, {returnBuffers: true});
    io.on('error', (err) => {
        console.log(err);
    });
    io.on('uncaughtException', (err) => {
        console.log(err);
    });
    io.adapter(redisAdapter({pubClient: pub, subClient: sub}));
    console.log('redis adapter started');
}
function addIOEventHandler(io) {
    //all the events for io
}

现在，我启动redis-server，然后用这个服务器启动node.js。然后我打开一个终端窗口，输入＆＃34; redis-cli shutdown＆＃34;强制redis服务器下线。一旦我这样做，node.js终端窗口就会一遍又一遍地循环遍历相同的错误。

events.js:154
  throw er; // Unhandled 'error' event
  ^

Error: Redis connection to 127.0.0.1:6379 failed - connect ECONNREFUSED 127.0.0.1:6379
    at Object.exports._errnoException (util.js:893:11)
    at exports._exceptionWithHostPort (util.js:916:20)
    at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1075:14)
redis adapter started with url: redis://127.0.0.1:6379

我有两个process.on（＆＃39; uncaughtException＆＃39; ...和io.on（＆＃39; uncaughtException＆＃39; ...以及io.on（＆＃39;错误＆＃39;，...处理程序，但每次服务器只是坐在那里循环说有一个＆＃34;未处理的＆＃39;错误＆＃39;事件＆＃34; 有人可以帮帮我吗。我不知道这可能是一个未处理的错误，但出于某种原因，它在我的脑海里并没有意义。提前感谢您提供任何可能的帮助。我一直在寻找互联网几个小时试图寻找任何其他可能的选择，他们都说同样的事情，使用io.on（＆＃39;错误＆＃39;或io.on（＆＃39; uncaughtException＆＃39） ;或者是process.on（＆＃39; uncaughtException＆＃39;，我拥有它们并且它仍然出错并崩溃节点。

Answer 1

感谢@SadiRubaiyet指出我正确的方向。我不得不向pub和sub添加一个错误事件。一旦我这样做，当redis关闭时不再有节点崩溃。这是编辑过的代码......

var cluster = require('cluster');
var express = require('express');
var http = require('http');
var redis = require('redis');
var redisAdapter = require('socket.io-redis');
var sticky = require('sticky-session');
var port = process.env.PORT || 3333;
var workers = 3;
var app = express();
var server = http.createServer(app);
var io = require('socket.io')(server);

if(!sticky.listen(server, 3333, {workers: workers})) {
    server.once('listening', () => {
        console.log('server started on port ' + port);
        process.on('exit', () => {
            io.emit('error', {errorType: 'SERVER_SHUTDOWN'});
        });
        process.on('uncaughtException', (err) => {
            console.log('uncaught exception occurred');
            console.log(err);
        });
    });
} else {
    addRedisAdapter(io);
    addIOEventHandler(io);
}

function addRedisAdapter(io) {
    var redisUrl = process.env.REDISTOGO_URL || 'redis://127.0.0.1:6379';
    var redisOptions = require('parse-redis-url')(redis).parse(redisUrl);
    var pub = redis.createClient(redisOptions.port, redisOptions.host, { returnBuffers: true});
    var sub = redis.createClient(redisOptions.port, redisOptions.host, {returnBuffers: true});
    io.on('error', (err) => {
        console.log(err);
    });
    io.on('uncaughtException', (err) => {
        console.log(err);
    });
    /*HERE IS THE NEW CODE THAT MADE IT WORK*/
    pub.on('error', (err) => {
        console.log('error from pub');
        console.log(err);
    });
    sub.on('error', (err) => {
        console.log('error from sub);
        console.log(err);
    });
    /*END*/
    io.adapter(redisAdapter({pubClient: pub, subClient: sub}));
    console.log('redis adapter started');
}
function addIOEventHandler(io) {
    //all the events for io
}

Answer 2

我使用此行解决了此问题：

 io.of('/').adapter.on('error', function(error){
          console.log('error: ', error);            
       });

redis-server offline崩溃节点

2 个答案: