How to write node.js web for multiple user?

Question

I wrote a basic web server

If the first user open 127.0.0.1/complex

and the second user open 127.0.0.1/simple

2nd user cannot see website until 1st user complete

How can I solve this problem?

var http = require('http');
var url = require('url');
http.createServer(function (req, res) {

    var pathname = url.parse(req.url).pathname;

    res.writeHead(200, {'Content-Type': 'text/plain'});

    if(pathname=='/complex')
    {
        console.log('complex');
        complexFunction(res);
    }
    else if(pathname=='/simple')
    {
        console.log('simple');
        simpleFunction(res);
    }
}).listen(80, '127.0.0.1');


function complexFunction(res)
{
    for(var i=0; i<9999999999; i++)
    {
        var complex=200000/3;
        complex*=200;
    }
    res.end('complex');
}
function simpleFunction(res)
{
    var simple=1;
    res.end('simple');
}

Just don't do such calculations. Or do them in a different thread, at least. — Bergi, Jan 17 '15 at 22:21
Node.js is single-threaded. Start reading here: http://stackoverflow.com/a/16974649/271150 — asp_net, Jan 17 '15 at 22:25

score 3 · Accepted Answer · answered Jan 17 '15 at 22:34

node.js is a single thread process and is designed for async programming. your for loop is blocking the whole process you need to split it up and make it asynchronous.

setImmediate() is one possibility or this. see: http://nodejs.org/api/timers.html#timers_setimmediate_callback_arg

var http = require('http');
var url = require('url');
http.createServer(function (req, res) {

    var pathname = url.parse(req.url).pathname;

    res.writeHead(200, {'Content-Type': 'text/plain'});

    if(pathname=='/complex')
    {
        console.log('complex');
        complexFunction(res, 9999999999);
    }
    else if(pathname=='/simple')
    {
        console.log('simple');
        simpleFunction(res);
    }
}).listen(80, '127.0.0.1');

function complexFunction(res, i)
{
   if(i >= 0)
   {
        i--;
        var complex=200000/3;
        complex*=200;

       setImmediate(function() { 
          complexFunction(res, i)
         });
    } else {
        res.end('complex');
    }
}

function simpleFunction(res)
{
    var simple=1;
    res.end('simple');
}

It works, but it makes the program very difficult to read. Now I understand why node.js is not suitable for website. — CL So, Jan 18 '15 at 18:56
@CLSo.. doesn't mean node is not suitable.. its just different than other languages — Naeem Shaikh, Jan 20 '15 at 11:17

How to write node.js web for multiple user?

1 Answers1