Uploaded File replacement functionality (in File & Media fields)

[macburgee1]

Here's a core issue: https://www.drupal.org/project/drupal/issues/2648816. There's been nothing meaningful happening there - no patches have been offered since the issue was opened in Jan 2016.

This module will take advantage of a proposed hook_file_upload() function: https://www.drupal.org/project/drupal/issues/3065698.

[macburgee1]

Let's take a look at the new Media Entity File Replace module. It sidesteps a number of issues I was running into.

In my initial testing, it works as I expected. Because it can only act on the edit form (and not on the add form), it shouldn't be possible to overwrite a file accidentally (e.g. file with same name already exists on another media entity.)

We'll need to figure out the external cache piece, however.

[macburgee1]

See code example from https://www.drupal.org/project/acquia_purge/issues/2911828#comment-12450381:

/**
 * Implements hook_entity_update().
 */
function my_module_entity_update(EntityInterface $entity) {
  $type = $entity->getEntityTypeId();
  if ($type != 'file') {
    return;
  }

  $purgeInvalidationFactory = \Drupal::service('purge.invalidation.factory');
  $purgeQueuers = \Drupal::service('purge.queuers');
  $purgeQueue = \Drupal::service('purge.queue');

  $queuer = $purgeQueuers->get('coretags');
  // Invalidate cache tags so all pages that have the file get banned from varnish
  // Also invalidate the file's url.
  $invalidations = [
    $purgeInvalidationFactory->get('tag', 'file:' . $entity->id()),
    $purgeInvalidationFactory->get('url', file_create_url($entity->getFileUri())),
  ];

  $purgeQueue->add($queuer, $invalidations);
}

It would be nice if the Media Entity File Replace module provided a hook for us to use as a trigger. That said, in media_entity_file_replace_entity_extra_field_info(), they check if $mediaType->getSource() instanceof File. If we can access that information from $entity, that would be a reasonable solution.

[ericras]

Media Entity File Replace added: 73fedef

That takes care of media file entities. Still an issue with plain file fields. Will will be using those? Direct devs who create custom content types to use media files?

Wiki started to contain these notes: https://github.com/unlcms/project-herbie/wiki/Site-Developer-Role-Notes