NGINX As a log for massive requests

Hi all,
i'm very new to NGINX.
I have a site and i want to count each time a user enters it.
Instead of keeping a counter on my site's server that will go up each time i serve a page i want to send add to my site a JS code that posts to a new server with nginx, sending the server a parameter.
The new server (the one with NGINX) will write to a constant file (each time a post is made to him) a line with the time and the parameter sent in the request.
I'll create a script that runs over the file and counts each entrance..

Since i'm getting massive traffic a friends told me that NGINX is suited best for my need, how can i use it in the best way?

Regards,
Guy