custom-prometheus-exporter/index.php

<?php

if($_SERVER["REQUEST_URI"] == '/metrics') {
    header('Content-Type: text/plain; version=0.0.4');
    $config = getenv('CONFIG_FILE');
    $phpbin = getenv('PHP_BINARY');
    $output = shell_exec('CONFIG_FILE="' . $config . '" ' . $phpbin . ' ' . $_SERVER['DOCUMENT_ROOT'] . '/script.php');
    echo $output;
} elseif ($_SERVER["REQUEST_URI"] == '/config') {
    header('Content-Type: application/json');
    require_once getenv('CONFIG_FILE');
    echo json_encode($config);
} elseif ($_SERVER["REQUEST_URI"] == '/version' && is_dir($_SERVER['DOCUMENT_ROOT'] . '/.git')) {
    header('Content-Type: application/json');
    $git = [
        'lastCommit' => trim(shell_exec('git rev-parse HEAD')),
        'lastCommitTimestamp' => trim(shell_exec('git log -1 --format=%cd')),
        'branch' => trim(shell_exec('git rev-parse --abbrev-ref HEAD')),
    ];
    echo json_encode($git);
} else {
    require_once('vendor/autoload.php');
    $knownpaths = [
        '/metrics',
        '/config'
    ];
    if (is_dir($_SERVER['DOCUMENT_ROOT'] . '/.git')) $knownpaths[] = '/version';
    http_response_code(404);
    $loader = new \Twig\Loader\FilesystemLoader('templates');
    $twig = new \Twig\Environment($loader, [
        'cache' => 'twig_cache',
    ]);
    echo $twig->render('404.twig', ['path' => $_SERVER["REQUEST_URI"], 'knownpaths' => $knownpaths]);
}