Source of all data collected

When using the matomo.js script, you fill out _paq and it sends all of its data to the endpoint you define – typically matomo.php. As part of the request matomo.js builds, it includes the various dimensions (if specified; e.g., dimension1, dimension2) and also variables such as idsite, _id, pf_net, et. al. matomo.php then takes all of that request data, builds up a profile, and stores that data in a table (e.g., piwik_log_visit) in the configured database.

I see that in a couple of places in the code, the $_COOKIE superglobal is used so I imagine that on top of $_REQUEST, $_COOKIE is also used in data collection to ultimately get stored in the database.

My question is this – does matomo.php use data from any other source when collecting data? Apart from $_REQUEST and, possibly, $_COOKIE? Because of how our system is set up, we need to configure the setTrackerUrl to one of our internal pages and we’d like to just aggregate the necessary data (from $_REQUEST at the very least and possibly $_COOKIE as well) and make our own curl request to matomo.php. However, we just want to make sure that we pass along all the data that matomo.php would need for a particular tracking request. So does matomo.php use anything from any of the other superglobals (e.g., $_SESSION)? Grepping through the codebase it doesn’t seem like it does but I’m just hoping for verification.

A somewhat related question is this – provided we pass the required information along in our curl request, that won’t affect generation of any of the reports, correct (e.g., Form Analytics, Heatmap & Session Recording, et. al.)?