Changeset 58579 for trunk/src/wp-includes/class-wp-script-modules.php

Timestamp:

06/26/2024 01:19:47 PM (2 years ago)

Author:

Bernhard Reiter

Message:

Script Modules: Add new API to embed server data in HTML.

Add a new filter script_module_data_{$module_id} to associate data
with a Script Module. For example:

add_filter(
        'script_module_data_MyScriptModuleID',
        function ( array $data ): array {
                $data['script-needs-this-data'] = 'ok';
                return $data;
        }
);

If the Script Module is included in the page, enqueued or as a
dependency, the associated data will be JSON-encoded and embedded in the
HTML in a <script type="application/json"> tag with an ID of the form
wp-script-module-data-{$module_id} allowing the Script Module to
access the data on the client.

See the original proposal: ​https://make.wordpress.org/core/2024/05/06/proposal-server-to-client-data-sharing-for-script-modules/

Developed in ​https://github.com/WordPress/wordpress-develop/pull/6682.

Props jonsurrell, cbravobernal, westonruter, gziolo, bernhard-reiter, youknowriad, sergiomdgomes, czapla.
Fixes #61510. See #60647.

File:

• trunk/src/wp-includes/class-wp-script-modules.php (modified) (2 diffs)

trunk/src/wp-includes/class-wp-script-modules.php

@@ -183 +183 @@
                 add_action( 'admin_print_footer_scripts', array( $this, 'print_enqueued_script_modules' ) );
                 add_action( 'admin_print_footer_scripts', array( $this, 'print_script_module_preloads' ) );
+
+                add_action( 'wp_footer', array( $this, 'print_script_module_data' ) );
+                add_action( 'admin_print_footer_scripts', array( $this, 'print_script_module_data' ) );
         }
 
@@ -364 +367 @@
                 return $src;
         }
+
+        /**
+         * Print data associated with Script Modules.
+         *
+         * The data will be embedded in the page HTML and can be read by Script Modules on page load.
+         *
+         * @since 6.7.0
+         *
+         * Data can be associated with a Script Module via the
+         * {@see "script_module_data_{$module_id}"} filter.
+         *
+         * The data for a Script Module will be serialized as JSON in a script tag with an ID of the
+         * form `wp-script-module-data-{$module_id}`.
+         */
+        public function print_script_module_data(): void {
+                $modules = array();
+                foreach ( array_keys( $this->get_marked_for_enqueue() ) as $id ) {
+                        $modules[ $id ] = true;
+                }
+                foreach ( array_keys( $this->get_import_map()['imports'] ) as $id ) {
+                        $modules[ $id ] = true;
+                }
+
+                foreach ( array_keys( $modules ) as $module_id ) {
+                        /**
+                         * Filters data associated with a given Script Module.
+                         *
+                         * Script Modules may require data that is required for initialization or is essential
+                         * to have immediately available on page load. These are suitable use cases for
+                         * this data.
+                         *
+                         * The dynamic portion of the hook name, `$module_id`, refers to the Script Module ID
+                         * that the data is associated with.
+                         *
+                         * This is best suited to pass essential data that must be available to the module for
+                         * initialization or immediately on page load. It does not replace the REST API or
+                         * fetching data from the client.
+                         *
+                         * @example
+                         *   add_filter(
+                         *     'script_module_data_MyScriptModuleID',
+                         *     function ( array $data ): array {
+                         *       $data['script-needs-this-data'] = 'ok';
+                         *       return $data;
+                         *     }
+                         *   );
+                         *
+                         * If the filter returns no data (an empty array), nothing will be embedded in the page.
+                         *
+                         * The data for a given Script Module, if provided, will be JSON serialized in a script
+                         * tag with an ID of the form `wp-script-module-data-{$module_id}`.
+                         *
+                         * The data can be read on the client with a pattern like this:
+                         *
+                         * @example
+                         *   const dataContainer = document.getElementById( 'wp-script-module-data-MyScriptModuleID' );
+                         *   let data = {};
+                         *   if ( dataContainer ) {
+                         *     try {
+                         *       data = JSON.parse( dataContainer.textContent );
+                         *     } catch {}
+                         *   }
+                         *   initMyScriptModuleWithData( data );
+                         *
+                         * @since 6.7.0
+                         *
+                         * @param array $data The data associated with the Script Module.
+                         */
+                        $data = apply_filters( "script_module_data_{$module_id}", array() );
+
+                        if ( is_array( $data ) && array() !== $data ) {
+                                /*
+                                 * This data will be printed as JSON inside a script tag like this:
+                                 *   <script type="application/json"></script>
+                                 *
+                                 * A script tag must be closed by a sequence beginning with `</`. It's impossible to
+                                 * close a script tag without using `<`. We ensure that `<` is escaped and `/` can
+                                 * remain unescaped, so `</script>` will be printed as `\u003C/script\u00E3`.
+                                 *
+                                 *   - JSON_HEX_TAG: All < and > are converted to \u003C and \u003E.
+                                 *   - JSON_UNESCAPED_SLASHES: Don't escape /.
+                                 *
+                                 * If the page will use UTF-8 encoding, it's safe to print unescaped unicode:
+                                 *
+                                 *   - JSON_UNESCAPED_UNICODE: Encode multibyte Unicode characters literally (instead of as `\uXXXX`).
+                                 *   - JSON_UNESCAPED_LINE_TERMINATORS: The line terminators are kept unescaped when
+                                 *     JSON_UNESCAPED_UNICODE is supplied. It uses the same behaviour as it was
+                                 *     before PHP 7.1 without this constant. Available as of PHP 7.1.0.
+                                 *
+                                 * The JSON specification requires encoding in UTF-8, so if the generated HTML page
+                                 * is not encoded in UTF-8 then it's not safe to include those literals. They must
+                                 * be escaped to avoid encoding issues.
+                                 *
+                                 * @see https://www.rfc-editor.org/rfc/rfc8259.html for details on encoding requirements.
+                                 * @see https://www.php.net/manual/en/json.constants.php for details on these constants.
+                                 * @see https://html.spec.whatwg.org/#script-data-state for details on script tag parsing.
+                                 */
+                                $json_encode_flags = JSON_HEX_TAG | JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_LINE_TERMINATORS;
+                                if ( ! is_utf8_charset() ) {
+                                        $json_encode_flags = JSON_HEX_TAG | JSON_UNESCAPED_SLASHES;
+                                }
+
+                                wp_print_inline_script_tag(
+                                        wp_json_encode(
+                                                $data,
+                                                $json_encode_flags
+                                        ),
+                                        array(
+                                                'type' => 'application/json',
+                                                'id'   => "wp-script-module-data-{$module_id}",
+                                        )
+                                );
+                        }
+                }
+        }
 }