Get node based target id from entity reference

Question

We have an Article content type which has an Entity Reference field called field_document that is linked to the Media bundle type of Document. In mymodule we need to write a hook that will take the current field_document.id (which maps to Document.mid) and return all the Article pages where field_document.target_id = mid.

Goal

• Take the current node id and retrieve the Document entity that is linked to by accessing field_document
• Using the field_document value, return other Articles that have the same value for field_document
• Perform the query in a hook_preprocess_node() hook.

Question

1. How can we retrieve all the nodes based on the $mid?

When we tried

We were able to return all Articles. However when we add ->condition('field_document.target_id, $mid), we get zero results even though we know there are Articles where the field_document.target_id = $mid.

function mymodule_preprocess_node($variables) {
  $node = $variables['node'];
  $linked_document_id = $node->get('field_document')->first()->getValue()['target_id'];

  $node_storage = \Drupal::entityTypeManager()->getStorage('node');
  $query = $node_storage->getQuery()
    ->condition('type', 'article')
    ->condition('status', 1);

  $and = $query->andConditionGroup();
  $and->condition('field_document', $linked_document_id, '=');
  $query->condition($and);
  $results = $query->execute();

  // returns zero
  ksm($results);
}

We also tried using $and->condition('field_document.target_id', $linked_document_id, '=');, but that did not return any results either.

Additional steps we tried, but with similar issue.

 function mymodule_preprocess_node($variables) {
  $node = $variables['node'];
  $linked_document_id = $node->get('field_document')->first()->getValue()['target_id'];

  $node_storage = \Drupal::entityTypeManager()->getStorage('node');
  $query = $node_storage->getQuery()
    ->condition('type', 'article')
    ->condition('status', 1);
    ->condition('field_document', $linked_document_id, '=');
  $results = $query->execute();

  // returns zero
  ksm($results);
}

Answer 1

We found the issue, it was both duplicate data issue and syntax errors mentioned by @berramou. The fix to the query was changing ->condition('status', 1); line to ->condition('status', 1).

We found that the test data included duplicate media entities so when the ->condition('field_document', $linked_document_id, '='); was added, there were no results because the entities we were expecting were not in the table.

Sample test data:

• media entity (id=1) name --> foo
• media entity (id=2) name --> foo

• media entity (id=3) name --> bar

• Article->field_document->target_id = 1

I was expecting foo (id=1) to be returned but I was receiving foo (id=2). We have a specific requirement that media entities should be unique so after we merged the duplicate ones, the issue resolved.

function mymodule_preprocess_node($variables) {
  $node = $variables['node'];
  $linked_document_id = $node->get('field_document')->first()->getValue()['target_id'];

  $node_storage = \Drupal::entityTypeManager()->getStorage('node');
  $query = $node_storage->getQuery()
    ->condition('type', 'article')
    ->condition('status', 1)
    ->condition('field_document', $linked_document_id, '=');
  $results = $query->execute();

  // returns results now
  ksm($results);
}