Intercept http requests without creating a browser extension

Question

I'm currently trying to create an application to automate analytics testing, but I have no idea what to use or how to start. What I wanted to do is explained in the pic below

I want to read the headers because the request that corresponds to the analytics have specific attributes. Is it possible to access those requests without creating an extension? ( Preferably with jQuery or PHP )

Answer 1

In php you can use getallheaders() ,

<?php
    foreach (getallheaders() as $name => $value) {
        echo "$name: $value\n";
    }
?>