Get Pantheon public database credentials for external integration

get_creds.php

<?php

/**
 * This is a script to retrieve DB credentials for database connections
 *
 */

/**
 * Check IP address function
 */
function checkIPAddress()
{
  $allowed_ips_array = file(getcwd() . "/private/dbcr/allowed_ips.txt", FILE_IGNORE_NEW_LINES) or die("Unable to open ip list file!");
  $ipArrayLength = count($allowed_ips_array);
  if ($ipArrayLength > 0) {
    if (in_array($_SERVER['REMOTE_ADDR'], $allowed_ips_array)) {
      return true;
    } else {
      header("HTTP/1.0 404 Not Found");
      exit;
    }
  } else {
    return true;
  }
}

/**
 * Check authorization function
 */
function checkAuthCreds($posted_password)
{
  $auth_password_object = fopen(getcwd() . "/private/dbcr/creds_pass.txt", "r") or die("Unable to open authorization file!");
  $auth_password = fgets($auth_password_object);
  $auth_password = str_replace("\r\n", "", $auth_password);
  $auth_password = str_replace("\r", "", $auth_password);
  $auth_password = str_replace("\n", "", $auth_password);
  fclose($auth_password_object);
  if ($posted_password == $auth_password) {
    getDBCreds();
  } else {
    print $posted_password;
    print $auth_password;
    print "Invalid credentials.";
    exit;
  }
}

/**
 * Retrieve DB Credentials
 */
function getDBCreds()
{
  if (isset($_ENV['PANTHEON_ENVIRONMENT']) || isset($_ENV['LANDO_DOMAIN'])) {
    if (function_exists('pantheon_curl')) {
      $url = 'https://api.live.getpantheon.com/sites/self/variables';
      $req = pantheon_curl($url, NULL, 8443);
      $meta = json_decode($req['body'], true);

      // Extract DB credentials
      $db = json_encode([
        'DB_USER' => $meta['username'],
        'DB_PASSWORD' => $meta['password'],
        'DB_HOST' => $meta['ideal_host'],
        'DB_PORT' => $meta['port'],
        'DB_NAME' => $meta['database']
      ]);

      print($db);
    }
  } else {
    die("This script will not run outside of the Pantheon Platform");
  }
}

/**
 * Init function to start execution of the script
 */
function credsInit()
{
  if (isset($_GET['password'])) {
    checkAuthCreds($_GET['password']);
  } else {
    print "Missing parameters.";
    exit;
  }
}

// Initiate the execution of the script.

// First, let's make sure Pantheon CDN does not cache these results
header("Cache-Control: no-store, no-cache, must-revalidate, max-age=0");

// Set the Content-Type header to application/json.
header('Content-Type: application/json');

// Now let's execute...
credsInit();