Question

My node js like that but when i start this server, it meet te error :

and my node version is v0.6.18.
and i follow the suggestion as
possible EventEmitter memory leak detected

add req.setMaxListeners(0)
but it doesn’t work.

i attach my whole code here :

        var express = require('../node_modules/express'),
        redis = require('../node_modules/socket.io/node_modules/redis'), 
        // io = require('../node_modules/socket.io').listen(app),
        fs = require('fs');

    var app = express.createServer();
    app.use(express.bodyParser());

    var cache = redis.createClient(7010, "192.168.100.18");

    var port = 8888;

    // get html page ok
    app.get('/*', function (req, res) {
        req.setMaxListeners(0);
        res.sendfile(__dirname + '/html/' + req.params[0]);
    });

    // get js page ok
    app.get('/js/*', function (req, res){
        res.sendfile(__dirname + '/html/js/' + req.params[0]);
    });

    // get image ok
    app.get('/img/*', function (req, res){
        res.sendfile(__dirname + '/html/img/' + req.params[0]);
    });

    // login interface ok
    app.post('/login*', function(req, res, next){
        console.log("access login")
        var username = req.body.username;
        var password = req.body.password;

        if(username == null || password == null){
            console.log("username or password is nil")
            res.json({ret:false})
            return
        }

        cache.hget("margin:user:password", username, function(err, resp){
            if (err != null){
                console.log(err)
            }
            if(resp == null){
                res.json({ret:false})
                return
            }
            res.json({ret:true})
            return
        })
    });

    // upload file interface ok
    app.post('/upload*', function(req, res, next){
        console.log(req.files)
        console.log(req.body)
        fs.readFile(req.files.image.path, function(err, data){
            var unix = Math.round(+new Date()/1000);
            var imagename = unix + "." + req.files.image.type.split("/")[1]
            var newPath = __dirname + "/html/img/" + imagename;
            fs.writeFile(newPath, data, function(err){
                if(err == null){
                    res.json({ret:true, img:"http://192.168.100.188:" + port + "/html/img/" + imagename});
                    return;
                }
                res.json({ret:false});
            });
        });
    });

    app.listen(port);

my request url like localhost:8888/index.html

thanks a lot.

add error:

    (node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit.
Trace: 
    at Socket.<anonymous> (events.js:139:15)
    at ServerResponse.sendfile (/data/www/margintop/server/node_modules/express/lib/response.js:185:14)
    at /data/www/margintop/server/webserver/webserver.js:17:9
    at callbacks (/data/www/margintop/server/node_modules/express/lib/router/index.js:165:11)
    at param (/data/www/margintop/server/node_modules/express/lib/router/index.js:139:11)
    at pass (/data/www/margintop/server/node_modules/express/lib/router/index.js:146:5)
    at Router._dispatch (/data/www/margintop/server/node_modules/express/lib/router/index.js:173:4)
    at Object.router [as handle] (/data/www/margintop/server/node_modules/express/lib/router/index.js:33:10)
    at next (/data/www/margintop/server/node_modules/express/node_modules/connect/lib/proto.js:190:15)
    at multipart (/data/www/margintop/server/node_modules/express/node_modules/connect/lib/middleware/multipart.js:52:61)

Answer 1

I believe this is a bug in express. Line 185 of response.js reads:

req.socket.on('error', error);

But this listener doesn’t get removed. This bug seems to have been introduced recently.

I have added a pull request to express which fixes this.
For a quick fix, you can add

this.on('finish', function() { req.socket.removeListener('error', error); });

after line 220 of your /data/www/margintop/server/node_modules/express/lib/response.js to make it look like this:

res.sendfile = function(path, options, fn){

  // ...

  // socket errors
  req.socket.on('error', error);

  // ...

  this.on('finish', function() { req.socket.removeListener('error', error); });
};

Update

My pull request has been merged, so the bug is fixed in the latest source version of express.