How can I get the submission ID in a custom submit handler?

Question

I have added a submission handler in a .module file to execute some custom code when a webform is submitted.

function mh_newsletter_form_alter(&$form, $form_state, $form_id) {
  if ($form_id == 'webform_submission_newsletter_node_26_add_form') {
    $form['#validate'][] = 'mh_newsletter_form_validate';
    $form['actions']['submit']['#submit'][] = 'mh_newsletter_form_submit';
  }
}

function mh_newsletter_form_submit($form, &$form_state) {
  // Custom code
}

I'm unable to access the webform submission ID. How can I get that value?

Answer 1

To get the webform submission ID in a custom form handler, I used the following code.

function MODULE_form_alter(&$form, \Drupal\Core\Form\FormStateInterface $form_state, $form_id) {
  if ($form_id== 'webform_submission_add_form') {
    $form['actions']['submit']['#submit'][] = 'MODULE_custom_submit_handler';
  }
}

function MODULE_custom_submit_handler(&$form, \Drupal\Core\Form\FormStateInterface $form_state) {
  $webform_submission_id = $form_state->getFormObject()->getEntity()->id();
 }

Answer 2

Add a webform handler to the webform configuration and use the method submitForm() of the handler, which provides the submission entity as argument:

mymodule/src/Plugin/WebformHandler/MyWebformHandler.php:

<?php

namespace Drupal\mymodule\Plugin\WebformHandler;

use Drupal\Core\Form\FormStateInterface;
use Drupal\webform\Plugin\WebformHandlerBase;
use Drupal\webform\WebformSubmissionInterface;

/**
 * My webform submission handler.
 *
 * @WebformHandler(
 *   id = "my_webform_handler",
 *   label = @Translation("My Webform Handler"),
 *   category = @Translation("Example"),
 *   description = @Translation("Example of a webform handler."),
 *   cardinality = \Drupal\webform\Plugin\WebformHandlerInterface::CARDINALITY_SINGLE,
 *   results = \Drupal\webform\Plugin\WebformHandlerInterface::RESULTS_PROCESSED,
 *   submission = \Drupal\webform\Plugin\WebformHandlerInterface::SUBMISSION_OPTIONAL,
 * )
 */
class MyWebformHandler extends WebformHandlerBase {

  /**
   * {@inheritdoc}
   */
  public function submitForm(array &$form, FormStateInterface $form_state, WebformSubmissionInterface $webform_submission) {
    $submission_id = $webform_submission->id();
    // my submit logic
  }

}