Nodejs web server calling requestListener twice when page is loaded

Question

Hey guys, I am trying out node.js, the following is the example web server from the documentation with an added counter and it prints the counter to the console when ever a client/browser requests the page.

The problem is, its being called twice when requested by the browser.

This is what I would expect would happen:

browser : Hello World 1
console : Counter 1
[reload page]
browser : Hello World 2
console : Counter 2

but this happens:

browser : Hello World 1
console : Counter 1
          Counter 2
[reload page]
browser : Hello World 3
console : Counter 3
          Counter 4

I run the code using the command line

$ node example.js

Here is the code:

  var 
    http = require('http'),
    counter = 0,
    sys = require('util');
  http.createServer(function (req, res) {
    res.writeHead(200, {'Content-Type': 'text/plain'});
    counter++;
    res.end('Hello World ' + counter + '\n');
    sys.puts('Counter ' + counter);
  }).listen(8000, "");

Any help is appreciated.

Thanks

Answer 1

In programming, when stuck, it's always handy to trace the code to better understand what's happening. The easiest way to do this is to put more debug/print statements in till you can see what's going on.

Change the sys.puts line to:

sys.puts('Counter ' + counter + " from " + req.url);

I think you'll find that the 2nd request is the browser requesting the favicon for the site.