I need to remove a resource object (in this case a paragraph) from a JSON:API response when it matches a specific condition. I do not want to delete it, I just want to exclude the object from the response.

Approach: I tried using a FieldEnhancer to access the resource object in "doUndoTransform()", check for the condition and skip/remove it before being displayed.

Problem: So far I only succeeded in altering the data of my resource object. I’m able to manipulate its content but I haven’t yet figured out how to exclude it from the output.

Question: Is there any way or probably an alternative (to the FieldEnhancer approach) to achieve my goal? I thought about extending the schema in "getOutputJsonSchema()" but due to a lack of documentation I’m missing the possible options.

Setup:

Article (node) | List (paragraph) | Items | Item (paragraph containing my custom FieldGroup with criteria) (see below)

My FieldEnhancer is attached to List looping over each Item in Items to retrieve the entity ID and the condition. The custom FieldGroup which holds the condition can be attached to any entity so using a FieldEnhancer on a specific resource is also pretty fast.

FieldEnhancer code example:

/**  * {@inheritdoc}  */ protected function doUndoTransform($data, Context $context): mixed {     $entityId = $this->getEntityId($context);     // if ok display object     if ($this->fieldGroupProcessor->isCondition($entityId)) {        return $data;     }      // else return null / skip / remove object }  public function getOutputJsonSchema(): array {     return [         'type' => 'object',         'properties' => [],     ]; } 

JSON:API resource object example:

{ type: "paragraph--quicklinks", id: "3eabd16d-92a5-468d-9968-ad7e24797340", links: {     self: {         href: "http://127.0.0.1:8088/jsonapi/paragraph/quicklinks/3eabd16d-92a5-468d-9968-ad7e24797340"     } }, attributes: {     heading: "Test" }, relationships: {     quicklinks_items: {         data: [{             type: "paragraph--quicklink_item",             id: "af04ef25-bee5-401d-b5f7-1bf742349dde",             meta: {                 target_revision_id: 230829,                 drupal_internal__target_id: 36089             }         },         {             type: "paragraph--quicklink_item",             id: "0831315b-f6bd-46a4-87bf-feff5c9473bc",             meta: {                 target_revision_id: 230831,                 drupal_internal__target_id: 36091             }         },         {             type: "paragraph--quicklink_item",             id: "53b2a7d2-4388-4e5f-8681-a91cbe0e07c7",             meta: {                 target_revision_id: 230833,                 drupal_internal__target_id: 36301             }         }],         links: {             related: {                 href: "http://127.0.0.1:8088/jsonapi/paragraph/quicklinks/3eabd16d-92a5-468d-9968-ad7e24797340/quicklinks_items"             },             self: {                 href: "http://127.0.0.1:8088/jsonapi/paragraph/quicklinks/3eabd16d-92a5-468d-9968-ad7e24797340/relationships/quicklinks_items"             }         }     } } 

},