Entityreference not saved correctly inside ContentEntityForm

Question

I was having a weird bug with my views. Some entity-references from my main-entity didn't show up in my view.

I investigated further with entityQuery and came across some weird action. I can get the missing referenced entities by querying for nulls in main_entity and loading the referenced entities manually using the magic entity getter:

// Returns 90 main-entities. These correspond to the entities with missing data in my view.
$main_entity_ids = \Drupal::entityQuery('main_entity')
  ->notExists('field_referenced_entity')
  ->sort('created')
  ->execute();
$main_entities = \Drupal\my_module\Entity\MainEntity::loadMultiple($main_entity_ids);

// Load referenced entities for each main entity using the magic entity getter
$referenced_entities = [];
foreach($main_entities as $main_id => $main_entity){
  // Skip nulls
  if($referenced_entity = $main_entity->get('field_referenced_entity')->entity){
    $referenced_entities[$referenced_entity->id()] = $referenced_entity;

    // // Re-saving the entity here doesn't help
    // $main_entity->set('field_referenced_entity', $referenced_entity->id())
    // $main_entity->save();
  }
}

// At this point $referenced_entities -array contains 90 fully loaded refenced entities.

Also, the table main_entity__field_referenced_entity is missing rows for the missing references. I wonder how am I able to get the reference with the magic getter.

I tried to re-save all the entities in my loop but with no success.

The main-entity is first created and saved without the reference which is added afterwards inside ContentEntityForm::save()-method.

...
// Entity is saved and re-loaded
$main_entity->save();
$main_entity = \Drupal\my_module\Entity\MainEntity::load($id);
...
// Set the reference and save
$main_entity->set('field_referenced_entity', 123);
$main_entity->save();
...

Creating the MainEntity programmatically seems to work, inserting the required rows to the main_entity__field_referenced_entity -table:

$main_entity = \Drupal\my_module\Entity\MainEntity::create([
  'type' => 'main_entity',
  'status' => 1,
  'name' => 'Programmatically created MainEntity',
]);
$main_entity->save(); // No rows
$main_entity = \Drupal\my_module\Entity\MainEntity::load($main_entity->id());
$main_entity->set('field_referenced_entity', 123);
$main_entity->save(); // Row added

The problem seems to have started after updating to Drupal 8.5 from 8.4.4. I was running Drupal 8.5.3 when I noticed the problem. Updating to Drupal 8.5.5 doesn't help.

Does anyone have any idea what could be going on?

Answer 1

Found the cause!

Someone had added the line

$this->getReferencedEntity();

to the MainEntity::__construct()-method.

getReferencedEntity()-method uses some database-magic to find the reference and then set it to the MainEntity.

This worked fine before Drupal 8.5 but it seems that after that the system thought it already had the reference and didn't bother to insert it to the database.