Debug Incoming HTTP Requests

debug.php

<?php

function debugHttpRequest($filename, $mode = FILE_APPEND, $json = false)
{
    $output = '[' . date('Y-m-d H:i:s') . '] '
        . $_SERVER['REQUEST_METHOD'] . ' '
        . $_SERVER['REQUEST_URI']
        . "\n\n";

    foreach ($_SERVER as $key => $value) {
        $header = '';
        if (strpos($key, 'HTTP_') === 0 || in_array($key, ['CONTENT_TYPE'])) {
            $chunks = explode('_', $key);
            $start  = (strpos($key, 'HTTP_') === 0) ? 1 : 0;
            for ($i = $start; $y = sizeof($chunks) - 1, $i < $y; $i++) {
                $header .= ucfirst(strtolower($chunks[$i])).'-';
            }
            $header .= ucfirst(strtolower($chunks[$i])).': '.$value;
            $output .= $header."\n";
        }
    }

    $body = file_get_contents('php://input');

    if ($body != '') {
        if ($json || (isset($_SERVER['CONTENT_TYPE']) && stripos($_SERVER['CONTENT_TYPE'], 'json') !== false)) {
            if (json_decode($body) !== null) {
                $output .= "\n" . $body . "\n\n";
            } else {
                parse_str($body, $data);
                if (count($data) > 0) {
                    $output .= "\n" . json_encode($data, JSON_PRETTY_PRINT) . "\n\n";
                } else {
                    $output .= "\n" . $body . "\n\n";
                }
            }
        } else {
            $output .= "\n" . $body . "\n\n";
        }
    } else {
        $output .= "\n\n";
    }

    file_put_contents($filename, $output, $mode);
}

index.php

<?php

require __DIR__.'/debug.php';
debugHttpRequest('/tmp/req.log', FILE_APPEND, true);

/** FRAMEWORK STUFF BELOW */