REST API: Avoid unnecessarily preparing item links.

Do not call the `prepare_links` methods in core REST API controllers, unless the `_links` or `_embedded` fields are requested. There is no need to prepare links if they are never returned in the response. This saves resources, as many calls to `prepare_links` methods perform database queries. 

Props Spacedmonkey, timothyblynjacobs, rachelbaker, desrosj, dlh, hellofromTonya.
Fixes #52992.
Built from https://develop.svn.wordpress.org/trunk@53760


git-svn-id: http://core.svn.wordpress.org/trunk@53319 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/rest-api/endpoints/class-wp-rest-application-passwords-controller.php

@@ -610,6 +610,8 @@ class WP_REST_Application_Passwords_Controller extends WP_REST_Controller {
 			return $user;
 		}
 
+		$fields = $this->get_fields_for_response( $request );
+
 		$prepared = array(
 			'uuid'      => $item['uuid'],
 			'app_id'    => empty( $item['app_id'] ) ? '' : $item['app_id'],
@@ -627,7 +629,10 @@ class WP_REST_Application_Passwords_Controller extends WP_REST_Controller {
 		$prepared = $this->filter_response_by_context( $prepared, $request['context'] );
 
 		$response = new WP_REST_Response( $prepared );
+
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $user, $item ) );
+		}
 
 		/**
 		 * Filters the REST API response for an application password.

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

@@ -119,6 +119,8 @@ class WP_REST_Block_Directory_Controller extends WP_REST_Controller {
 		// Restores the more descriptive, specific name for use within this method.
 		$plugin = $item;
 
+		$fields = $this->get_fields_for_response( $request );
+
 		// There might be multiple blocks in a plugin. Only the first block is mapped.
 		$block_data = reset( $plugin['blocks'] );
 
@@ -146,7 +148,10 @@ class WP_REST_Block_Directory_Controller extends WP_REST_Controller {
 		$this->add_additional_fields_to_object( $block, $request );
 
 		$response = new WP_REST_Response( $block );
+
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $plugin ) );
+		}
 
 		return $response;
 	}

wp-includes/rest-api/endpoints/class-wp-rest-block-types-controller.php

@@ -306,7 +306,9 @@ class WP_REST_Block_Types_Controller extends WP_REST_Controller {
 
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $block_type ) );
+		}
 
 		/**
 		 * Filters a block type returned from the REST API.

wp-includes/rest-api/endpoints/class-wp-rest-comments-controller.php

@@ -1119,7 +1119,9 @@ class WP_REST_Comments_Controller extends WP_REST_Controller {
 		// Wrap the data in a response object.
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $comment ) );
+		}
 
 		/**
 		 * Filters a comment returned from the REST API.

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

@@ -581,6 +581,18 @@ abstract class WP_REST_Controller {
 
 		$fields = array_keys( $properties );
 
+		/*
+		 * '_links' and '_embedded' are not typically part of the item schema,
+		 * but they can be specified in '_fields', so they are added here as a
+		 * convenience for checking with rest_is_field_included().
+		 */
+		$fields[] = '_links';
+		if ( $request->has_param( '_embed' ) ) {
+			$fields[] = '_embedded';
+		}
+
+		$fields = array_unique( $fields );
+
 		if ( ! isset( $request['_fields'] ) ) {
 			return $fields;
 		}

wp-includes/rest-api/endpoints/class-wp-rest-global-styles-controller.php

@@ -392,6 +392,7 @@ class WP_REST_Global_Styles_Controller extends WP_REST_Controller {
 		// Wrap the data in a response object.
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$links = $this->prepare_links( $post->ID );
 			$response->add_links( $links );
 			if ( ! empty( $links['self']['href'] ) ) {
@@ -401,6 +402,7 @@ class WP_REST_Global_Styles_Controller extends WP_REST_Controller {
 					$response->add_link( $rel, $self );
 				}
 			}
+		}
 
 		return $response;
 	}
@@ -590,13 +592,14 @@ class WP_REST_Global_Styles_Controller extends WP_REST_Controller {
 
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$links = array(
 				'self' => array(
 					'href' => rest_url( sprintf( '%s/%s/themes/%s', $this->namespace, $this->rest_base, $request['stylesheet'] ) ),
 				),
 			);
-
 			$response->add_links( $links );
+		}
 
 		return $response;
 	}

wp-includes/rest-api/endpoints/class-wp-rest-menu-items-controller.php

@@ -610,6 +610,7 @@ class WP_REST_Menu_Items_Controller extends WP_REST_Posts_Controller {
 		// Wrap the data in a response object.
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$links = $this->prepare_links( $item );
 			$response->add_links( $links );
 
@@ -622,6 +623,7 @@ class WP_REST_Menu_Items_Controller extends WP_REST_Posts_Controller {
 					$response->add_link( $rel, $self );
 				}
 			}
+		}
 
 		/**
 		 * Filters the menu item data for a REST API response.

wp-includes/rest-api/endpoints/class-wp-rest-menu-locations-controller.php

@@ -193,7 +193,9 @@ class WP_REST_Menu_Locations_Controller extends WP_REST_Controller {
 
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $location ) );
+		}
 
 		/**
 		 * Filters menu location data returned from the REST API.

wp-includes/rest-api/endpoints/class-wp-rest-menus-controller.php

@@ -134,7 +134,10 @@ class WP_REST_Menus_Controller extends WP_REST_Terms_Controller {
 		$data    = $this->filter_response_by_context( $data, $context );
 
 		$response = rest_ensure_response( $data );
+
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $term ) );
+		}
 
 		/** This action is documented in wp-includes/rest-api/endpoints/class-wp-rest-terms-controller.php */
 		return apply_filters( "rest_prepare_{$this->taxonomy}", $response, $term, $request );

wp-includes/rest-api/endpoints/class-wp-rest-plugins-controller.php

@@ -576,6 +576,8 @@ class WP_REST_Plugins_Controller extends WP_REST_Controller {
 	 * @return WP_REST_Response|WP_Error Response object on success, or WP_Error object on failure.
 	 */
 	public function prepare_item_for_response( $item, $request ) {
+		$fields = $this->get_fields_for_response( $request );
+
 		$item   = _get_plugin_data_markup_translate( $item['_file'], $item, false );
 		$marked = _get_plugin_data_markup_translate( $item['_file'], $item, true );
 
@@ -600,7 +602,10 @@ class WP_REST_Plugins_Controller extends WP_REST_Controller {
 		$data = $this->add_additional_fields_to_object( $data, $request );
 
 		$response = new WP_REST_Response( $data );
+
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $item ) );
+		}
 
 		/**
 		 * Filters plugin data for a REST API response.

wp-includes/rest-api/endpoints/class-wp-rest-post-types-controller.php

@@ -244,7 +244,9 @@ class WP_REST_Post_Types_Controller extends WP_REST_Controller {
 		// Wrap the data in a response object.
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $post_type ) );
+		}
 
 		/**
 		 * Filters a post type returned from the REST API.

wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php

@@ -1933,6 +1933,7 @@ class WP_REST_Posts_Controller extends WP_REST_Controller {
 		// Wrap the data in a response object.
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$links = $this->prepare_links( $post );
 			$response->add_links( $links );
 
@@ -1945,6 +1946,7 @@ class WP_REST_Posts_Controller extends WP_REST_Controller {
 					$response->add_link( $rel, $self );
 				}
 			}
+		}
 
 		/**
 		 * Filters the post data for a REST API response.

wp-includes/rest-api/endpoints/class-wp-rest-search-controller.php

@@ -210,11 +210,13 @@ class WP_REST_Search_Controller extends WP_REST_Controller {
 
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$links               = $handler->prepare_item_links( $item_id );
 			$links['collection'] = array(
 				'href' => rest_url( sprintf( '%s/%s', $this->namespace, $this->rest_base ) ),
 			);
 			$response->add_links( $links );
+		}
 
 		return $response;
 	}

wp-includes/rest-api/endpoints/class-wp-rest-sidebars-controller.php

@@ -368,7 +368,9 @@ class WP_REST_Sidebars_Controller extends WP_REST_Controller {
 
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $sidebar ) );
+		}
 
 		/**
 		 * Filters the REST API response for a sidebar.

wp-includes/rest-api/endpoints/class-wp-rest-taxonomies-controller.php

@@ -272,7 +272,9 @@ class WP_REST_Taxonomies_Controller extends WP_REST_Controller {
 		// Wrap the data in a response object.
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $taxonomy ) );
+		}
 
 		/**
 		 * Filters a taxonomy returned from the REST API.

wp-includes/rest-api/endpoints/class-wp-rest-templates-controller.php

@@ -662,6 +662,7 @@ class WP_REST_Templates_Controller extends WP_REST_Controller {
 		// Wrap the data in a response object.
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$links = $this->prepare_links( $template->id );
 			$response->add_links( $links );
 			if ( ! empty( $links['self']['href'] ) ) {
@@ -671,6 +672,7 @@ class WP_REST_Templates_Controller extends WP_REST_Controller {
 					$response->add_link( $rel, $self );
 				}
 			}
+		}
 
 		return $response;
 	}

wp-includes/rest-api/endpoints/class-wp-rest-terms-controller.php

@@ -859,7 +859,9 @@ class WP_REST_Terms_Controller extends WP_REST_Controller {
 
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $item ) );
+		}
 
 		/**
 		 * Filters the term data for a REST API response.

wp-includes/rest-api/endpoints/class-wp-rest-themes-controller.php

@@ -331,7 +331,9 @@ class WP_REST_Themes_Controller extends WP_REST_Controller {
 		// Wrap the data in a response object.
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $theme ) );
+		}
 
 		/**
 		 * Filters theme data returned from the REST API.

wp-includes/rest-api/endpoints/class-wp-rest-users-controller.php

@@ -1072,7 +1072,9 @@ class WP_REST_Users_Controller extends WP_REST_Controller {
 		// Wrap the data in a response object.
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $user ) );
+		}
 
 		/**
 		 * Filters user data returned from the REST API.

wp-includes/rest-api/endpoints/class-wp-rest-widget-types-controller.php

@@ -335,7 +335,9 @@ class WP_REST_Widget_Types_Controller extends WP_REST_Controller {
 
 		$response = rest_ensure_response( $data );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $widget_type ) );
+		}
 
 		/**
 		 * Filters the REST API response for a widget type.

wp-includes/rest-api/endpoints/class-wp-rest-widgets-controller.php

@@ -726,7 +726,9 @@ class WP_REST_Widgets_Controller extends WP_REST_Controller {
 
 		$response = rest_ensure_response( $prepared );
 
+		if ( rest_is_field_included( '_links', $fields ) || rest_is_field_included( '_embedded', $fields ) ) {
 			$response->add_links( $this->prepare_links( $prepared ) );
+		}
 
 		/**
 		 * Filters the REST API response for a widget.

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.1-alpha-53759';
+$wp_version = '6.1-alpha-53760';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.