How to hide a webform field from a node display when the per-user submission limit has been reached

Question

I have a Webform field on my node, which links to an application form. The form is set to allow one submission per user (per node). I want the link to disappear after the user has submitted the form.

Any good ways to do this?

Answer 1

You can try to implement hook_entity_field_access

function hook_entity_field_access($operation, \Drupal\Core\Field\FieldDefinitionInterface $field_definition, \Drupal\Core\Session\AccountInterface $account, \Drupal\Core\Field\FieldItemListInterface $items = NULL) {
  if ($field_definition->getName() === 'field_registration_form' && $operation === 'view') {
  $webform = Webform::load('WEBFORM_ID');
  // Using webform config entity to check submission create.
  $access_result = $webform->access('submission_create', $account, TRUE);
  // Adding the current account as a cacheable dependency and the 'webform_submission_list' cache tag
  // to keep track of any new submission per user.
  $access_result->addCacheableDependency($account)
  ->addCacheTags('webform_submission_list');
  return $access_result;
  }
  return AccessResult::neutral();
}

Answer 2

This works (below, added to MY_THEME.theme), but I haven't stress-tested it:

function TEMPLATE_preprocess_node(&$variables) {
  // Hide field_registration_form if already submitted to it.
  if($variables['node']->bundle() == 'CONTENT_TYPE') {
    $current_user = \Drupal::currentUser();
    $uid = $current_user->id();
    $webform = Webform::load('WEBFORM_ID');
    if ($webform->hasSubmissions()) {
      $query = \Drupal::entityQuery('webform_submission')
        ->condition('webform_id', 'WEBFORM_ID');
      $result = $query->execute();
      $submission_data = [];
      foreach ($result as $item) {
        $submission = \Drupal\webform\Entity\WebformSubmission::load($item);
        $submission_data[] = $submission->getData()['user'];
      }
      if (in_array($uid, $submission_data)) {
        unset($variables['content']['field_registration_form']);
      }
    }
  }
}