REST API: Fixes `/wp/v2/pattern-directory/patterns` endpoint response for `slug` parameter.

[53218] introduced a bug of a wrong response from the `wp/v2/pattern-directory/patterns` endpoint with a `slug` parameter. As the response is cached, it can result in an incorrect list of available patterns supported by the current theme.

This commit resolves by:

* Limiting the `slug` to an `array` in the query parameters.
* When set, parsing and sorting the slug(s) and then serializing the sorted query args as part of the hashed transient keys.

Props antonvlasenko, timothyblynjacobs, spacedmonkey, costdev, hellofromTonya.

Follow-up to [53218], [53152], [51208].
Fixes #55617.
Built from https://develop.svn.wordpress.org/trunk@53333


git-svn-id: http://core.svn.wordpress.org/trunk@52922 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/rest-api/endpoints/class-wp-rest-pattern-directory-controller.php

@@ -119,16 +119,7 @@ class WP_REST_Pattern_Directory_Controller extends WP_REST_Controller {
 			$query_args['slug'] = $slug;
 		}
 
-		/*
-		 * Include a hash of the query args, so that different requests are stored in
-		 * separate caches.
-		 *
-		 * MD5 is chosen for its speed, low-collision rate, universal availability, and to stay
-		 * under the character limit for `_site_transient_timeout_{...}` keys.
-		 *
-		 * @link https://stackoverflow.com/questions/3665247/fastest-hash-for-non-cryptographic-uses
-		 */
-		$transient_key = 'wp_remote_block_patterns_' . md5( implode( '-', $query_args ) );
+		$transient_key = $this->get_transient_key( $query_args );
 
 		/*
 		 * Use network-wide transient to improve performance. The locale is the only site
@@ -337,6 +328,11 @@ class WP_REST_Pattern_Directory_Controller extends WP_REST_Controller {
 			'minimum'     => 1,
 		);
 
+		$query_params['slug'] = array(
+			'description' => __( 'Limit results to those matching a pattern (slug).' ),
+			'type'        => 'array',
+		);
+
 		/**
 		 * Filter collection parameters for the block pattern directory controller.
 		 *
@@ -346,4 +342,36 @@ class WP_REST_Pattern_Directory_Controller extends WP_REST_Controller {
 		 */
 		return apply_filters( 'rest_pattern_directory_collection_params', $query_params );
 	}
+
+	/*
+	 * Include a hash of the query args, so that different requests are stored in
+	 * separate caches.
+	 *
+	 * MD5 is chosen for its speed, low-collision rate, universal availability, and to stay
+	 * under the character limit for `_site_transient_timeout_{...}` keys.
+	 *
+	 * @link https://stackoverflow.com/questions/3665247/fastest-hash-for-non-cryptographic-uses
+	 *
+	 * @since 6.0.0
+	 *
+	 * @param array $query_args Query arguments to generate a transient key from.
+	 * @return string Transient key.
+	 */
+	protected function get_transient_key( $query_args ) {
+
+		if ( isset( $query_args['slug'] ) ) {
+			// This is an additional precaution because the "sort" function expects an array.
+			$query_args['slug'] = wp_parse_list( $query_args['slug'] );
+
+			// Empty arrays should not affect the transient key.
+			if ( empty( $query_args['slug'] ) ) {
+				unset( $query_args['slug'] );
+			} else {
+				// Sort the array so that the transient key doesn't depend on the order of slugs.
+				sort( $query_args['slug'] );
+			}
+		}
+
+		return 'wp_remote_block_patterns_' . md5( serialize( $query_args ) );
+	}
 }

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.0-beta3-53332';
+$wp_version = '6.0-beta3-53333';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.