Variable UPDB_PREAMBLE_PHPConst
UPDB_PREAMBLE_PHP: "\nuse Drupal\\Core\\DrupalKernel;\nuse Drupal\\Core\\Site\\Settings;\nuse Symfony\\Component\\HttpFoundation\\Request;\n\n// require rather than require_once: the latter returns TRUE on a second call, and a heap restore\n// reaches that state; see the note in site-php.ts\nif (!isset($GLOBALS['__pw_autoloader']) || !is_object($GLOBALS['__pw_autoloader'])) {\n\t$GLOBALS['__pw_autoloader'] = require '/drupal/autoload.php';\n}\n$autoloader = $GLOBALS['__pw_autoloader'];\n\nif (!isset($GLOBALS['__pw_kernel'])) {\n\t$bootRequest = Request::create('/', 'GET');\n\t$kernel = new DrupalKernel('prod', $autoloader);\n\tDrupalKernel::bootEnvironment();\n\t$sitePath = DrupalKernel::findSitePath($bootRequest);\n\t$kernel->setSitePath($sitePath);\n\tSettings::initialize('/drupal', $sitePath, $autoloader);\n\t$kernel->boot();\n\t$GLOBALS['__pw_kernel'] = $kernel;\n\t$out['bootedKernel'] = 1;\n}\n\ntry {\n\t$stack = Drupal::service('request_stack');\n\tif ($stack->getCurrentRequest() === null) {\n\t\t$stack->push(Request::create('/update.php', 'GET'));\n\t\t$out['pushedRequest'] = 1;\n\t}\n} catch (Throwable $e) {\n\t$out['requestStackError'] = get_class($e) . ': ' . $e->getMessage();\n}\n\nrequire_once '/drupal/core/includes/common.inc';\nrequire_once '/drupal/core/includes/install.inc';\nrequire_once '/drupal/core/includes/update.inc';\n// procedural hooks live in .module files, which a bare boot never includes: the cache_flush step\n// read scheduler_cache_flush as a class name and halted every Thunder update\nDrupal::moduleHandler()->loadAll();\ndrupal_load_updates();\n"