DrupalKernel::bootEnvironment

public static DrupalKernel::bootEnvironment($app_root = NULL)

public static function bootEnvironment($app_root = NULL) {
  if (static::$isEnvironmentInitialized) {
    return;
  }

  // Determine the application root if it's not supplied.
  if ($app_root === NULL) {
    $app_root = static::guessApplicationRoot();
  }

  // Include our bootstrap file.
  require_once $app_root . '/core/includes/bootstrap.inc';

  // Enforce E_STRICT, but allow users to set levels not part of E_STRICT.
  error_reporting(E_STRICT | E_ALL);

  // Override PHP settings required for Drupal to work properly.
  // sites/default/default.settings.php contains more runtime settings.
  // The .htaccess file contains settings that cannot be changed at runtime.

  // Use session cookies, not transparent sessions that puts the session id in
  // the query string.
  ini_set('session.use_cookies', '1');
  ini_set('session.use_only_cookies', '1');
  ini_set('session.use_trans_sid', '0');
  // Don't send HTTP headers using PHP's session handler.
  // Send an empty string to disable the cache limiter.
  ini_set('session.cache_limiter', '');
  // Use httponly session cookies.
  ini_set('session.cookie_httponly', '1');

  // Set sane locale settings, to ensure consistent string, dates, times and
  // numbers handling.
  setlocale(LC_ALL, 'C');

  // Detect string handling method.
  Unicode::check();

  // Indicate that code is operating in a test child site.
  if (!defined('DRUPAL_TEST_IN_CHILD_SITE')) {
    if ($test_prefix = drupal_valid_test_ua()) {
      $test_db = new TestDatabase($test_prefix);
      // Only code that interfaces directly with tests should rely on this
      // constant; e.g., the error/exception handler conditionally adds further
      // error information into HTTP response headers that are consumed by
      // Simpletest's internal browser.
      define('DRUPAL_TEST_IN_CHILD_SITE', TRUE);

      // Web tests are to be conducted with runtime assertions active.
      assert_options(ASSERT_ACTIVE, TRUE);
      // Now synchronize PHP 5 and 7's handling of assertions as much as
      // possible.
      Handle::register();

      // Log fatal errors to the test site directory.
      ini_set('log_errors', 1);
      ini_set('error_log', $app_root . '/' . $test_db->getTestSitePath() . '/error.log');

      // Ensure that a rewritten settings.php is used if opcache is on.
      ini_set('opcache.validate_timestamps', 'on');
      ini_set('opcache.revalidate_freq', 0);
    }
    else {
      // Ensure that no other code defines this.
      define('DRUPAL_TEST_IN_CHILD_SITE', FALSE);
    }
  }

  // Set the Drupal custom error handler.
  set_error_handler('_drupal_error_handler');
  set_exception_handler('_drupal_exception_handler');

  static::$isEnvironmentInitialized = TRUE;
}