MTKA-1542: Ensure relationship fields resolve if model slug mismatches singular label

CHANGELOG.md

@@ -12,6 +12,7 @@
 ### Fixed
 - Issue where adding a new repeating field to an existing model schema could break GraphQL queries under certain conditions.
 - Empty field values are no longer saved to the database.
+- Relationship fields no longer resolve as “null” in GraphQL results for models with different singular names and API identifiers.
 
 ### Added
 - Added email validation when using insert_model_entry() crud function.

includes/content-registration/custom-post-types-registration.php

@@ -659,6 +659,8 @@ function register_relationship_connection( array $parent_model, array $reference
 		array(
 			'from_type'  => camelcase( $parent_model['singular'] ),
 			'to_type'    => camelcase( $reference_model['singular'] ),
+			'from_slug'  => $parent_model['slug'],
+			'to_slug'    => $reference_model['slug'],
 			'slug'       => $field['slug'],
 			'one_to_one' => ( $field['cardinality'] === 'one-to-one' || $field['cardinality'] === 'many-to-one' ),
 			'reference'  => $field['reference'],
@@ -670,6 +672,8 @@ function register_relationship_connection( array $parent_model, array $reference
 		$connections[] = array(
 			'from_type'  => camelcase( $reference_model['singular'] ),
 			'to_type'    => camelcase( $parent_model['singular'] ),
+			'from_slug'  => $reference_model['slug'],
+			'to_slug'    => $parent_model['slug'],
 			'slug'       => $field['reverseSlug'],
 			'one_to_one' => false,
 			'reference'  => $parent_model['slug'],
@@ -690,8 +694,8 @@ function register_relationship_connection( array $parent_model, array $reference
 					$registry = \WPE\AtlasContentModeler\ContentConnect\Plugin::instance()->get_registry();
 
 					$relationship = $registry->get_post_to_post_relationship(
-						sanitize_key( $connection_args['to_type'] ),
-						sanitize_key( $connection_args['from_type'] ),
+						sanitize_key( $connection_args['to_slug'] ),
+						sanitize_key( $connection_args['from_slug'] ),
 						$connection_args['name']
 					);
 

tests/integration/api-validation/test-data/models.php

@@ -58,4 +58,32 @@
 		'plural'   => 'Attachments',
 		'fields'   => array(),
 	),
+	'different-slug' => array(
+		'show_in_rest'    => true,
+		'show_in_graphql' => true,
+		'singular'        => 'Custom Slug',
+		'plural'          => 'Custom Slugs',
+		'slug'            => 'different-slug',
+		'api_visibility'  => 'public',
+		'model_icon'      => 'dashicons-admin-post',
+		'description'     => 'Singular name differs from slug.',
+		'with_front'      => false,
+		'fields'          => [
+			'1630411590619' => [
+				'show_in_rest'    => true,
+				'show_in_graphql' => true,
+				'type'            => 'relationship',
+				'id'              => '1630411590619',
+				'position'        => '170000',
+				'name'            => 'many-to-many-Relationship',
+				'slug'            => 'manytoManyRelationship',
+				'required'        => false,
+				'minChars'        => '',
+				'maxChars'        => '',
+				'reference'       => 'different-slug',
+				'cardinality'     => 'many-to-many',
+				'description'     => '',
+			],
+		],
+	),
 );

tests/integration/api-validation/test-data/posts.php

@@ -1,4 +1,7 @@
 <?php
+
+use function WPE\AtlasContentModeler\API\add_relationship;
+
 /**
  * Saves mock post data for processing
  */
@@ -61,6 +64,27 @@ function create_test_posts( $test_class ) {
 		)
 	);
 
+	$ids['custom_slug_1'] = $test_class->factory->post->create(
+		array(
+			'post_status' => 'publish',
+			'post_type'   => 'different-slug',
+		)
+	);
+
+	$ids['custom_slug_2'] = $test_class->factory->post->create(
+		array(
+			'post_status' => 'publish',
+			'post_type'   => 'different-slug',
+		)
+	);
+
+	// Create a relationship between the two previous posts.
+	add_relationship(
+		$ids['custom_slug_1'],
+		'manytoManyRelationship', // The relationship field slug from models.php.
+		$ids['custom_slug_2']
+	);
+
 	return $ids;
 }
 

tests/integration/api-validation/test-graphql-model-data.php

@@ -195,6 +195,39 @@ public function test_graphql_query_result_has_custom_fields_data(): void {
 		}
 	}
 
+	public function test_graphql_query_resolves_relationship_field_with_different_model_singular_name_and_id(): void {
+		try {
+			$results = graphql(
+				[
+					'query' => '
+				{
+					customSlugs {
+						nodes {
+							databaseId
+							manytoManyRelationship {
+								edges {
+									node {
+										databaseId
+									}
+								}
+							}
+						}
+					}
+				}
+				',
+				]
+			);
+
+			self::assertArrayHasKey( 'databaseId', $results['data']['customSlugs']['nodes'][0] );
+
+			self::assertArrayHasKey( 'manytoManyRelationship', $results['data']['customSlugs']['nodes'][0] );
+			self::assertNotNull( $results['data']['customSlugs']['nodes'][0]['manytoManyRelationship']['edges'] );
+			self::assertEquals( $this->post_ids['custom_slug_1'], $results['data']['customSlugs']['nodes'][0]['manytoManyRelationship']['edges'][0]['node']['databaseId'] );
+		} catch ( Exception $exception ) {
+			throw new PHPUnitRunnerException( sprintf( __FUNCTION__ . ' failed with exception: %s', $exception->getMessage() ) );
+		}
+	}
+
 	public function test_graphql_create_mutations_accept_acm_fields_as_inputs(): void {
 		wp_set_current_user( 1 );
 		try {