addOperation example

  public function testNestedDrupalFormSubmit($value = 1) {
    // Set the batch and process it.     $batch_builder = (new BatchBuilder())
      ->addOperation('_batch_test_nested_drupal_form_submit_callback', [$value]);
    batch_set($batch_builder->toArray());
    return batch_process('batch-test/redirect');
  }

  /** * Fires a batch process without a form submission. * * @return \Symfony\Component\HttpFoundation\RedirectResponse|null * A redirect response if the batch is progressive. No return value otherwise. */
  public function testNoForm() {
    

  public function testSetFile() {
    $filename = dirname(__DIR__, 6) . '/core/modules/system/tests/modules/batch_test/batch_test.callbacks.inc';
    $this->assertIsNotCallable('_batch_test_callback_1');
    $this->assertIsNotCallable('_batch_test_finished_1');

    $batch = (new BatchBuilder())
      ->setFile($filename)
      ->setFinishCallback('_batch_test_finished_1')
      ->addOperation('_batch_test_callback_1', [])
      ->toArray();
    $this->assertEquals($filename, $batch['file']);
    $this->assertEquals([['_batch_test_callback_1', []]], $batch['operations']);
    $this->assertEquals('_batch_test_finished_1', $batch['finished']);
    $this->assertIsCallable('_batch_test_callback_1');
    $this->assertIsCallable('_batch_test_finished_1');
  }

  /** * Tests setting and adding libraries. * * @covers ::setLibraries */

    else {
      try {
        $sync_steps = $config_importer->initialize();
        $batch_builder = (new BatchBuilder())
          ->setTitle($this->t('Synchronizing configuration'))
          ->setFinishCallback([ConfigImporterBatch::class, 'finish'])
          ->setInitMessage($this->t('Starting configuration synchronization.'))
          ->setProgressMessage($this->t('Completed step @current of @total.'))
          ->setErrorMessage($this->t('Configuration synchronization has encountered an error.'));
        foreach ($sync_steps as $sync_step) {
          $batch_builder->addOperation([ConfigImporterBatch::class, 'process'], [$config_importer, $sync_step]);
        }

        batch_set($batch_builder->toArray());
      }
      catch (ConfigImporterException $e) {
        // There are validation errors.         $this->messenger()->addError($this->t('The configuration cannot be imported because it failed validation for the following reasons:'));
        foreach ($config_importer->getErrors() as $message) {
          $this->messenger()->addError($message);
        }
      }
    }

foreach (['projects', 'disabled_projects'] as $type) {
      if (!$form_state->isValueEmpty($type)) {
        $projects = array_merge($projects, array_keys(array_filter($form_state->getValue($type))));
      }
    }
    $batch_builder = (new BatchBuilder())
      ->setFile($this->moduleHandler->getModule('update')->getPath() . '/update.manager.inc')
      ->setTitle($this->t('Downloading updates'))
      ->setInitMessage($this->t('Preparing to download selected updates'))
      ->setFinishCallback('update_manager_download_batch_finished');
    foreach ($projects as $project) {
      $batch_builder->addOperation('update_manager_batch_project_get', [
        $project,
        $form_state->getValue(['project_downloads', $project]),
      ]);
    }
    batch_set($batch_builder->toArray());
  }

}

  /** * {@inheritdoc} */
  public function submitForm(array &$form, FormStateInterface $form_state) {
    $config['source_base_path'] = $this->store->get('source_base_path');
    $config['source_private_file_path'] = $this->store->get('source_private_file_path');
    $batch_builder = (new BatchBuilder())
      ->setTitle($this->t('Running upgrade'))
      ->setProgressMessage('')
      ->addOperation([
        MigrateUpgradeImportBatch::class,
        'run',
      ], [array_keys($this->migrations), $config])
      ->setFinishCallback([MigrateUpgradeImportBatch::class, 'finished']);
    batch_set($batch_builder->toArray());
    $form_state->setRedirect('<front>');
    $this->store->set('step', 'overview');
    $this->state->set('migrate_drupal_ui.performed', REQUEST_TIME);
  }

  /** * {@inheritdoc} */

/** * {@inheritdoc} */
  public function submitForm(array &$form, FormStateInterface $form_state) {
    $entity_type_id = $form_state->getValue('entity_type_id');

    $entity_type_plural = $this->entityTypeManager->getDefinition($entity_type_id)->getPluralLabel();
    $batch_builder = (new BatchBuilder())
      ->setTitle($this->t('Deleting @entity_type_plural', ['@entity_type_plural' => $entity_type_plural]))
      ->setProgressMessage('')
      ->setFinishCallback([__CLASS__, 'moduleBatchFinished'])
      ->addOperation([__CLASS__, 'deleteContentEntities'], [$entity_type_id]);
    batch_set($batch_builder->toArray());
  }

  /** * Deletes the content entities of the specified entity type. * * @param string $entity_type_id * The entity type ID from which data will be deleted. * @param array|\ArrayAccess $context * The batch context array, passed by reference. * * @internal * This batch callback is only meant to be used by this form. */

    else {
      try {
        $sync_steps = $config_importer->initialize();
        $batch_builder = (new BatchBuilder())
          ->setTitle($this->t('Importing configuration'))
          ->setFinishCallback([ConfigImporterBatch::class, 'finish'])
          ->setInitMessage($this->t('Starting configuration import.'))
          ->setProgressMessage($this->t('Completed @current step of @total.'))
          ->setErrorMessage($this->t('Configuration import has encountered an error.'));
        foreach ($sync_steps as $sync_step) {
          $batch_builder->addOperation([ConfigImporterBatch::class, 'process'], [$config_importer, $sync_step]);
        }
        batch_set($batch_builder->toArray());
      }
      catch (ConfigImporterException $e) {
        // There are validation errors.         $this->messenger()->addError($this->t('The configuration import failed for the following reasons:'));
        foreach ($config_importer->getErrors() as $message) {
          $this->messenger()->addError($message);
        }
      }
    }
  }

    return $build;
  }

  /** * Manually checks the update status without the use of cron. */
  public function updateStatusManually() {
    $this->updateManager->refreshUpdateData();
    $batch_builder = (new BatchBuilder())
      ->setTitle(t('Checking available update data'))
      ->addOperation([$this->updateManager, 'fetchDataBatch'], [])
      ->setProgressMessage(t('Trying to check available update data ...'))
      ->setErrorMessage(t('Error checking available update data.'))
      ->setFinishCallback('update_fetch_data_finished');
    batch_set($batch_builder->toArray());
    return batch_process('admin/reports/updates');
  }

}

// Determine updates to be performed.     foreach ($updates as $function => $update) {
      if ($update['allowed']) {
        // Set the installed version of each module so updates will start at the         // correct place. (The updates are already sorted, so we can simply base         // this on the first one we come across in the above foreach loop.)         if (isset($start[$update['module']])) {
          \Drupal::service('update.update_hook_registry')->setInstalledVersion($update['module'], $update['number'] - 1);
          unset($start[$update['module']]);
        }
        $batch_builder->addOperation('update_do_one', [$update['module'], $update['number'], $dependency_map[$function]]);
      }
    }

    $post_updates = $this->postUpdateRegistry->getPendingUpdateFunctions();

    if ($post_updates) {
      // Now we rebuild all caches and after that execute the hook_post_update()       // functions.       $batch_builder->addOperation('drupal_flush_all_caches', []);
      foreach ($post_updates as $function) {
        $batch_builder->addOperation('update_invoke_post_update', [$function]);
      }