Support RDFa output in entity reference field formatter

It doesn't matter which schema.org property you use for the test, http://schema.org/mentions is fine, or you could also use http://schema.org/knows (say in the context of a social network built on Drupal).

@lokapujya correct.

@lokapujya there shouldn't be a need to implement a new method in EntityReferenceEntityFormatter, you should be able to support this in viewElements() right next to where we handle $item->attributes. In fact all that should be needed is to add that resource attribute to $item->_attributes, something like this:

$item->_attributes += array('resource' => 'node/1');

+++ b/core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/Field/FieldFormatter/EntityReferenceEntityFormatter.php
@@ -101,6 +101,7 @@ public function viewElements(FieldItemListInterface $items) {
+        $item->_attributes += array('resource' => 'node/' . $item->target_id);

First, check if $item->_attributes is not empty, since we don't need to do anything unless it has a property attribute. Then, just use $entity->url(). Don't forget to add a comment similar to this: Since we don't know what the markup of the entity will be, we shouldn't rely on it for structured data such as RDFa. Add a resource attribute to explicitly set the url of the entity as the value for this mapping property.

+++ b/core/modules/rdf/lib/Drupal/rdf/Tests/Field/EntityReferenceRdfaTest.php
@@ -0,0 +1,95 @@
+  /**
+   * The term for testing.
+   *
+   * @var \Drupal\taxonomy\Entity\Term
+   */
+  protected $target_entity;
+

This should be more accurate: The target entity for testing.

I tried with:

    entity_create('field_instance_config', array(
      'entity_type' => 'entity_test',
      'field_name' => $this->fieldName,
      'bundle' => 'entity_test',
      'settings' => array(
        'handler' => 'default',
        'handler_settings' => array(
          'target_bundles' => array('entity_test' => 'entity_test'),
        ),
      ),
    ))->save();

but it didn't make any difference to the output of the entity_reference_label or entity_reference_entity_id formatters.

Wow! Great job Jamie! It's passing the tests :) I will review by our next sprint on Tue!

1. +++ b/core/lib/Drupal/Core/Field/EntityReferenceFieldItemList.php
   
   +++ b/core/lib/Drupal/Core/Field/EntityReferenceFieldItemListInterface.php
   

   Looks like these files are irrelevant here.

2. +++ b/core/modules/entity_reference/lib/Drupal/entity_reference/Plugin/Field/FieldFormatter/EntityReferenceEntityFormatter.php
   @@ -114,6 +114,12 @@ public function viewElements(FieldItemListInterface $items) {
   +        // entity's url. Since we don't know what the markup of the entity will
   +        // be, we shouldn't rely on the markup for structured data such as RDFa.
   

   we shouldn't rely on *it* for structured data.

3. +++ b/core/modules/rdf/lib/Drupal/rdf/Tests/Field/FieldRdfaTestBase.php
   @@ -115,5 +115,8 @@ protected function createTestField() {
   diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
   
   diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
   old mode 100644
   new mode 100755
    
   

   that file shouldn't be part of the patch.

This needs to be rerolled for PSR-4

32: support-rdfa-output-in-entity-reference-2188895-32.patch queued for re-testing.

looks like we're missing the test which was present in #30.

looks like #2183231: Make ContentEntityDatabaseStorage generate static database schemas for content entities introduced a change? either way, the test is passing if I use

    $this->installEntitySchema('entity_test_rev');

instead of

    $this->installSchema('entity_test', array('entity_test_rev', 'entity_test_rev_revision'));

Looks great, glad you found the culprit that was causing the URI issue.

+++ b/core/vendor/symfony/http-foundation/Symfony/Component/HttpFoundation/Session/Storage/Proxy/AbstractProxy.php
@@ -120,7 +120,7 @@ public function getId()
-            throw new \LogicException('Cannot change the ID of an active session');
+            //throw new \LogicException('Cannot change the ID of an active session');

we should remove that :)

This looks good to go, except for this minor comment:

+++ b/core/modules/entity_reference/src/Plugin/Field/FieldFormatter/EntityReferenceLabelFormatter.php
@@ -76,6 +76,14 @@ public function viewElements(FieldItemListInterface $items) {
+            // Unset field item attributes since they have been included in the
+            // formatter output and should not be rendered in the field template.

This won't pass coding standards, it's > 80 chars. compacting should not to shouldn't should make it fit on the same line...

Thanks Jamie!