php://input
php://input is a special read-only stream that gives access the raw body of an incoming HTTP request. It does not work with CLI environment.
When a browser sends data to the web server, PHP parses it into superglobals like $_POST. But sometimes the exact raw payload is needed: that’s where php://input comes in.
The raw data used to be accessed via $HTTP_RAW_POST_DATA, but this is a deprecated feature.
<?php
$incoming = file_get_contents('php://input');
?>