big_pipe_test.module

<?php


/**
 * @file
 * Support module for BigPipe testing.
 */

/**
 * Implements hook_page_top().
 */
function big_pipe_test_page_top(array &$page_top) {
    // Ensure this hook is invoked on every page load.
    $page_top['#cache']['max-age'] = 0;
    $request = \Drupal::request();
    if ($request->query
        ->get('trigger_session')) {
        $request->getSession()
            ->set('big_pipe_test', TRUE);
    }
}