"PostBin" is a simple server that logs all requests to files in TEMP. Partially based on https://gist.github.com/magnetikonline/650e30e485c0f91f2f40

_README.md

How to run

php -S 0.0.0.0:3001 postbin.php

postbin.php

<?php

function getHeaderList() {
	$headerList = [];
	foreach ($_SERVER as $name => $value) {
		if (preg_match('/^HTTP_/',$name)) {
			// convert HTTP_HEADER_NAME to Header-Name
			$name = strtr(substr($name,5),'_',' ');
			$name = ucwords(strtolower($name));
			$name = strtr($name,' ','-');
			// add to list
			$headerList[$name] = $value;
		}
	}
	return $headerList;
}

// IMPORTANT NOTE: This filename format limits you to a single request per second.
// If multiple requests come in a single second, THEY WILL OVERWRITE EACH OTHER.
$filename = sys_get_temp_dir() . DIRECTORY_SEPARATOR . 'postbin-' . date('Ymdhis') . '.txt';

$handle = fopen($filename, 'w');

$data = sprintf(
	"%s %s %s" . PHP_EOL,
	$_SERVER['REQUEST_METHOD'],
	$_SERVER['REQUEST_URI'],
	$_SERVER['SERVER_PROTOCOL']
);
fwrite($handle, $data);

foreach (getHeaderList() as $name => $value) {
	fwrite($handle, $name . ': ' . $value . PHP_EOL);
}

fwrite($handle, PHP_EOL);

fwrite($handle, file_get_contents('php://input'));

fclose($handle);

header('X-Filepath: ' . $filename);