Ticket #49116: 49116.2.diff

src/wp-includes/class-wp-taxonomy.php

@@ -202 +202 @@
         /**
          * The controller for this taxonomy's REST API endpoints.
          *
-         * Custom controllers must extend WP_REST_Controller.
+         * Custom controllers must extend WP_REST_Controller. Should be accessed using {@see WP_Taxonomy::get_rest_controller()}.
          *
          * @since 4.7.4
          * @var string|bool $rest_controller_class
@@ -452 +452 @@
         public function remove_hooks() {
                 remove_filter( 'wp_ajax_add-' . $this->name, '_wp_ajax_add_hierarchical_term' );
         }
+
+
+        /**
+         * Gets the REST API controller for this taxonomy.
+         *
+         * Will only instantiate the controller class once per request.
+         *
+         * @since 5.5.0
+         *
+         * @return WP_REST_Controller|null The controller instance, or null if the taxonomy
+         *                                 is set not to show in rest.
+         */
+        public function get_rest_controller() {
+                if ( ! $this->show_in_rest ) {
+                        return null;
+                }
+
+                $class = $this->rest_controller_class ? $this->rest_controller_class : WP_REST_Terms_Controller::class;
+
+                if ( ! class_exists( $class ) ) {
+                        return null;
+                }
+
+                if ( ! is_subclass_of( $class, WP_REST_Controller::class ) ) {
+                        return null;
+                }
+
+                if ( ! $this->rest_controller ) {
+                        $this->rest_controller = new $class( $this->name );
+                }
+
+                if ( ! ( $this->rest_controller instanceof $class ) ) {
+                        return null;
+                }
+
+                return $this->rest_controller;
+        }
 }

src/wp-includes/default-filters.php

@@ -284 +284 @@
 add_action( 'wp_head', 'wp_resource_hints', 2 );
 add_action( 'wp_head', 'feed_links', 2 );
 add_action( 'wp_head', 'feed_links_extra', 3 );
+add_action( 'wp_head', 'rest_add_resource_link', 4 );
 add_action( 'wp_head', 'rsd_link' );
 add_action( 'wp_head', 'wlwmanifest_link' );
 add_action( 'wp_head', 'adjacent_posts_rel_link_wp_head', 10, 0 );

src/wp-includes/rest-api.php

@@ -1776 +1776 @@
 
         return $data;
 }
+
+
+/**
+ * Outputs a header link to a REST resource
+ *
+ * @since 5.5.0
+ *
+ * @param string       $url URL.
+ */
+function rest_head_link( $url ) {
+        if ( ! empty( $url ) ) {
+                printf( '<link rel="alternate" type="application/json" href="%s" />', esc_url( $url ) );
+        }
+}
+
+/**
+ * Return the rest route for a post.
+ *
+ * @since 5.5.0
+ *
+ * @param WP_Post       $post Post Object.
+ * @return string           Route.
+ */
+function rest_get_route_for_post( $post ) {
+        if ( ! $post instanceof WP_Post ) {
+                return '';
+        }
+
+        $post_type = get_post_type_object( $post->post_type );
+        if ( ! $post_type ) {
+                return '';
+        }
+
+        $route = '';
+        $controller = $post_type->get_rest_controller();
+
+        // The only two controllers that we can detect are the Attachments and Posts controllers.
+        if ( ! empty( $controller )  && in_array( $controller, array( 'WP_REST_Attachments_Controller', 'WP_REST_Posts_Controller' ), true ) ) {
+                $namespace = 'wp/v2';
+                $rest_base = ! empty( $post_type->rest_base ) ? $post_type->rest_base : $post_type->name;
+                $route = sprintf( '%s/%s/%d', $namespace, $rest_base, $post->ID );
+        }
+
+        /**
+         * Filters the route based on information in the post object.
+         *
+         * @since 5.5.0
+         *
+         * @param string $route Route.
+         * @param WP_Post $post Post Object.
+         */
+        return apply_filters( 'rest_route_for_post', $route, $post );
+}
+
+/**
+ * Return the rest route for a term.
+ *
+ * @since 5.5.0
+ *
+ * @param WP_Term       $term Term.
+ * @return string           Route.
+ */
+function rest_get_route_for_term( $term ) {
+        if ( ! $term instanceof WP_Term ) {
+                return '';
+        }
+        
+        $taxonomy = get_taxonomy( $term->taxonomy );
+        if ( ! $taxonomy ) {
+                return '';
+        }
+
+        $route = '';
+        $controller = $taxonomy->get_rest_controller();
+        // The only controller that works is the Terms controller.
+        if ( ! empty( $controller ) && 'WP_REST_Terms_Controller' === $controller ) {
+                $namespace = 'wp/v2';
+                $rest_base = ! empty( $taxonomy->rest_base ) ? $taxonomy->rest_base : $taxnomomy->name;
+                $route = sprintf( '%s/%s/%d', $namespace, $rest_base, $term->term_id );
+        }
+
+        /**
+         * Filters the route based on information in the term object.
+         *
+         * @since 5.5.0
+         *
+         * @param string $route Route.
+         * @param WP_Term $term Term Object.
+         */
+        return apply_filters( 'rest_route_for_term', $route, $term );
+}
+
+/**
+ * Get a REST URL for the current object.
+ *
+ * @param string URL.
+ */
+function rest_get_current_resource_link() {
+        if ( is_singular() ) {
+                return rest_url( rest_get_route_for_post( get_post() ) );
+        } elseif ( is_category() || is_tag() || is_tax() ) {
+                return rest_url( rest_get_route_for_term( get_queried_object() );
+        } elseif ( is_author() ) {
+                return rest_url( 'wp/v2/users/' . get_the_author_meta( 'ID' ) );
+        }
+}
+
+/**
+ * Add a link to the current REST API resource.
+ *
+ * @since 5.5.0
+ *
+ */
+function rest_add_resource_link() {
+        rest_head_link( rest_get_current_resource_link() );
+}