[EXPERIMENTAL] react-i18n: client-side locale switching

docs/manifest.json

@@ -1751,6 +1751,12 @@
 		"markdown_source": "../packages/project-management-automation/README.md",
 		"parent": "packages"
 	},
+	{
+		"title": "@wordpress/react-i18n",
+		"slug": "packages-react-i18n",
+		"markdown_source": "../packages/react-i18n/README.md",
+		"parent": "packages"
+	},
 	{
 		"title": "@wordpress/react-native-aztec",
 		"slug": "packages-react-native-aztec",

lib/class-wp-rest-translations-controller.php

@@ -0,0 +1,87 @@
+<?php
+/**
+ * REST API: WP_REST_Translations_Controller class
+ *
+ * @package Gutenberg
+ */
+
+/**
+ * Core class representing a controller for translations.
+ */
+class WP_REST_Translations_Controller extends WP_REST_Controller {
+	/**
+	 * Constructor.
+	 */
+	public function __construct() {
+		$this->namespace = '__experimental';
+		$this->rest_base = 'translations';
+	}
+
+	/**
+	 * Registers the widget routes for the controller.
+	 */
+	public function register_routes() {
+		register_rest_route(
+			$this->namespace,
+			$this->rest_base,
+			array(
+				array(
+					'methods'             => WP_REST_Server::READABLE,
+					'callback'            => array( $this, 'get_item' ),
+					'permission_callback' => array( $this, 'get_item_permissions_check' ),
+					'args'                => array(
+						'locale' => array(
+							'description' => __( 'Locale', 'gutenberg' ),
+							'type'        => 'string',
+						),
+						'handles' => array(
+							'description' => __( 'Script Handles', 'gutenberg' ),
+							'type'        => 'array',
+							'required'    => true,
+							'items'       => array(
+								'type' => 'string',
+							),
+						),
+						'context' => $this->get_context_param( array( 'default' => 'view' ) ),
+					),
+				),
+				'allow_batch' => array( 'v1' => true ),
+				'schema'      => array( $this, 'get_public_item_schema' ),
+			)
+		);
+	}
+
+	public function get_item_permissions_check( $request ) {
+		return true;
+	}
+
+	public function get_item( $request ) {
+		$switched = $request['locale'] && switch_to_locale( $request['locale'] );
+
+		$result = array();
+
+		foreach( $request['handles'] as $handle ) {
+			if ( ! isset( wp_scripts()->registered[ $handle ] ) ) {
+				continue;
+			}
+
+			/* @var \_WP_Dependency $script */
+			$script = wp_scripts()->registered[ $handle ];
+
+			if( ! $script ) {
+				continue;
+			}
+
+			$translations = load_script_textdomain( $handle, $script->textdomain, $script->translations_path );
+			if ( $translations ) {
+				$result[ $handle ] = json_decode( $translations );
+			}
+		}
+
+		if( $switched ) {
+			restore_previous_locale();
+		}
+
+		return $result;
+	}
+}

lib/client-assets.php

@@ -94,6 +94,18 @@ function gutenberg_override_script( $scripts, $handle, $src, $deps = array(), $v
 	 */
 	if ( 'wp-i18n' !== $handle && 'wp-polyfill' !== $handle ) {
 		$scripts->set_translations( $handle, 'default' );
+
+		if ( $script && 'wp-react-i18n' !== $handle ) {
+//			$script->deps[] = 'wp-react-i18n';
+
+			$data = <<<JS
+( function( handle ) {
+	wp?.reactI18n?.addHandle( handle );
+} )( "{$handle}" );
+JS;
+
+			$scripts->add_inline_script( $handle, $data );
+		}
 	}
 }
 

lib/load.php

@@ -59,6 +59,9 @@ function gutenberg_is_experiment_enabled( $name ) {
 	if ( ! class_exists( 'WP_REST_Batch_Controller' ) ) {
 		require_once __DIR__ . '/class-wp-rest-batch-controller.php';
 	}
+	if ( ! class_exists( 'WP_REST_Translations_Controller' ) ) {
+		require_once __DIR__ . '/class-wp-rest-translations-controller.php';
+	}
 	/**
 	* End: Include for phase 2
 	*/

lib/rest-api.php

@@ -51,6 +51,15 @@ function gutenberg_register_batch_endpoint() {
 }
 add_action( 'rest_api_init', 'gutenberg_register_batch_endpoint' );
 
+/**
+ * Registers the Translations REST API routes.
+ */
+function gutenberg_register_translations_endpoint() {
+	$translations = new WP_REST_Translations_Controller();
+	$translations->register_routes();
+}
+add_action( 'rest_api_init', 'gutenberg_register_translations_endpoint' );
+
 /**
  * Hook in to the nav menu item post type and enable a post type rest endpoint.
  *