Add optional pass_target_id argument to

[seth-shaw-asu]

GitHub Issue: asulibraries/islandora-repo#549

What does this Pull Request do?

Adds an optional 'pass_target_id' parameter to the EntityReferenceConverter::linkFieldPassthrough that allows us to pass through the target ID OR an empty string if it couldn't load the target ID's taxonomy term. This prevents errors from popping up in the watchdog for rest_oai_pmh and JSON-LD when an invalid target shows up.

What's new?

• Adds an optional 'pass_target_id' parameter to the EntityReferenceConverter::linkFieldPassthrough that allows us to pass through the target ID OR an empty string if it couldn't load the target ID's taxonomy term.
• Does this change require documentation to be updated? No
• Does this change add any new dependencies? No
• Does this change require any other modifications to be made to the repository
  (i.e. Regeneration activity, etc.)? No
• Could this change impact execution of existing code? No

How should this be tested?

A description of what steps someone could take to:

• Make or reuse a taxonomy with URIs
• Update the RDF mapping to use the linkFieldPassthrough converter, e.g.

  field_standard_rights:
    properties:
      - 'dcterms:rights'
    datatype_callback:
      callable: 'Drupal\jsonld\EntityReferenceConverter::linkFieldPassthrough'
      arguments:
        link_field: field_source

• Make a node with an entity reference for this field that is invalid. This is easiest to do using drush php:cli to load an existing node and update the field, e.g.:

$node = \Drupal::entityTypeManager()->getStorage('node')->load(3);
$node->field_standard_rights[] = ['target_id'=> 0];
$node->save();

• View the JSON-LD or OAI-PMH endpoint
• Now check your logs and you should see an error complaining about 'target_id'.
• Apply the patch
• Clear cache
• Reload either the JSON-LD or OAI-PMH feed.
• Check the logs, there shouldn't be any new errors.
• Even further: update your RDF mapping to pass the target_id, e.g.:

  field_standard_rights:
    properties:
      - 'dcterms:rights'
    datatype_callback:
      callable: 'Drupal\jsonld\EntityReferenceConverter::linkFieldPassthrough'
      arguments:
        link_field: field_source
        pass_target_id: true

• Clear cache and view the item again. Now the invalid target_id will show up as the value for the configured field.

Interested parties

@Islandora/8-x-committers

[whikloj]

Is there anywhere we are expecting the entity returned if it can't be converted?

[seth-shaw-asu]

Is there anywhere we are expecting the entity returned if it can't be converted?

Not that I'm aware of.

[whikloj]

@seth-shaw-asu how exactly does this error show up without defining the linkFieldPassThrough in the RDF mapping? I tried to use the instructions before adding that section and I do not see an error appearing. Just trying to see the original issue.

[seth-shaw-asu]

The error appears due to a bug with linkFieldPassThrough, so if you don't have it the error won't appear. This fix is adding the additional parameter to return a valid value if the original linkFieldPassThrough code fails.

[whikloj]

🤦 for some reason I saw that as new code and not a change, mea culpa.

[whikloj]

I'm using the playbook and field_standard_rights does not exist on the Repository Item. Is this custom or is it new and I have to use ISLE to test this?

[seth-shaw-asu]

It was custom. It doesn't really matter what taxonomy and reference field you use, as long as the target taxonomy has a Link/URI field.

For example, you could test this with Media using the Media Use field; you would just configure the RDF mapping for the media to use the passthrough plugin on the Media Use field and add the field_external_uri as the field parameter:

  field_media_use:
    properties:
      - 'pcdm:use'
    datatype_callback:
      callable: 'Drupal\jsonld\EntityReferenceConverter::linkFieldPassthrough'
      arguments:
        link_field: field_external_uri

Then you would make a Media with an invalid field_media_of reference:

$media = \Drupal::entityTypeManager()->getStorage('media')->load(1); # Or whichever media you are testing with...
$media->field_media_use[] = ['target_id'=> 0];
$media->save();

Then check the Media's JSON-LD. It should throw errors before the patch and work afterward.

Note: I didn't test this example, but all the same principles apply.

[whikloj]

Ok, this is not causing errors for me. I added an EntityReference field to islandora_object called 'field_standard_rights'. I linked it to a taxonomy that has a field_external_uri. I added a new object and added a "right" linked to a taxonomy term.

I altered the RDF mapping to add this section

field_standard_rights:
    properties:
      - 'dcterms:rights'
    datatype_callback:
      callable: 'Drupal\jsonld\EntityReferenceConverter::linkFieldPassthrough'
      arguments:
        link_field: field_external_uri
    mapping_type: rel

When I go into drush php:cli:

$node = \Drupal::entityTypeManager()->getStorage('node')->load(1);
=> Drupal\node\Entity\Node {#8454
     +in_preview: null,
     #nid: Drupal\Core\Field\FieldItemList {#8015},
 ...
     #field_weight: Drupal\Core\Field\FieldItemList {#8278},
   }
>>> $node->field_standard_rights[0]->getValue();
=> [
     "target_id" => "36",
   ]

I then altered it

>>> $node->field_standard_rights[0]->setValue(0);
=> null
>>> $node->save();
<warning>PHP Deprecated:  Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407 in /var/www/html/drupal/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php on line 116</warning>
<warning>PHP Deprecated:  Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407 in /var/www/html/drupal/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php on line 116</warning>
<warning>PHP Deprecated:  Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407 in /var/www/html/drupal/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php on line 116</warning>
<warning>PHP Deprecated:  Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407 in /var/www/html/drupal/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php on line 116</warning>
=> 2

But I still don't see any error in my log when I view the node as JSON-LD. 🤷 I can change it back to target_id = 36 and then I see the taxonomy term in the normal View and the URI in the JSON-LD view.

[whikloj]

I just tried

>>> $node = \Drupal::entityTypeManager()->getStorage('node')->load(1);
=> Drupal\node\Entity\Node {#5738
     +in_preview: null,
     #nid: Drupal\Core\Field\FieldItemList {#5691},
...
     #field_weight: Drupal\Core\Field\FieldItemList {#8275},
   }
>>> $node->field_standard_rights[0]->getValue();
=> [
     "target_id" => "36",
   ]
>>> $node->field_standard_rights[0]->setValue(["target_id" => "0"]);
=> null
>>> $node->save();
<warning>PHP Deprecated:  Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407 in /var/www/html/drupal/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php on line 116</warning>
<warning>PHP Deprecated:  Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407 in /var/www/html/drupal/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php on line 116</warning>
<warning>PHP Deprecated:  Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407 in /var/www/html/drupal/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php on line 116</warning>
<warning>PHP Deprecated:  Calling the Symfony\Component\EventDispatcher\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407 in /var/www/html/drupal/web/core/lib/Drupal/Component/EventDispatcher/ContainerAwareEventDispatcher.php on line 116</warning>
=> 2

But that also doesn't seem to cause any errors. I'm definitely missing something, but I don't know what it is.

[seth-shaw-asu]

I went back and tried to replicate the error w/ JSON-LD and I can't either. 😕 I threw a few statements in and discovered that these invalid values aren't being sent to the data_callback at all anymore, although it isn't clear what changed since I encountered this error on our servers. However, the other bit this patch does for JSON-LD is fall back to the referenced entity's label if the URI doesn't exist. To test, reference a term that doesn't have a URI value and you will see the label there instead.

That said, the rest_oai_pmh plugin does still throw errors without this patch when you try to view the record using the RDF Mapping plugin.

[whikloj]

Works as described on OAI-PMH requests. 👍