Render whole entity inside a controller

Question

I am trying to print an entity reference field (from paragraphs module) into a controller.
I learned from this ticket that you can use
{{ teacher.field_classrooms.entity.field_in_paragraph.value }} to get the value of one field from the entity, but what I really need is to print the whole entity not just one field from the entity.

I was hoping to do something like {{ teacher.field_classrooms.entity }} rather than {{ teacher.field_classrooms.entity.field_in_paragraph.value }} {{ teacher.field_classrooms.entity.field_different_in_paragraph.value }}.

Answer 1

You can do that by setting a variable in your controller or in template_preprocess_teacher in your .theme file, like:

function template_preprocess_teacher(array &$variables) {
  $classrooms = $variables['elements'][0]->get('field_classrooms')->referencedEntities(); //probably a bit different for paragraphs ..

  foreach($classrooms as $classroom) {
    $variables['classrooms'][] = \Drupal::entityTypeManager()->getViewBuilder($classroom->getEntityTypeId())->view($classroom, 'optional-view-mode');
  }
}

And then access it in twig like this:

{{ classrooms }}

If you're looking for a twig only solution use the twig_tweak module, then it comes down to this:

{% for field_in_paragraph in teacher.field_classrooms.entity %}
  {{ drupal_entity('classroom', field_in_paragraph.value, 'optional-view-mode') }}
{% endfor %}