Blocks: Add handling for block.json viewModule

lib/experimental/modules/class-gutenberg-modules.php

@@ -280,3 +280,191 @@
 
 // Prints the script that loads the import map polyfill in the footer.
 add_action( 'wp_head', array( 'Gutenberg_Modules', 'print_import_map_polyfill' ), 11 );
+
+/**
+ * Add module fields from block metadata to WP_Block_Type settings.
+ *
+ * This filter allows us to register modules from block metadata and attach additional fields to
+ * WP_Block_Type instances.
+ *
+ * @param array $settings Array of determined settings for registering a block type.
+ * @param array $metadata Metadata provided for registering a block type.
+ */
+function gutenberg_filter_block_type_metadata_settings_register_modules( $settings, $metadata = null ) {
+	$module_fields = array(
+		'viewModule' => 'view_module_ids',
+	);
+	foreach ( $module_fields as $metadata_field_name => $settings_field_name ) {
+		if ( ! empty( $settings[ $metadata_field_name ] ) ) {
+			$metadata[ $metadata_field_name ] = $settings[ $metadata_field_name ];
+		}
+		if ( ! empty( $metadata[ $metadata_field_name ] ) ) {
+			$modules           = $metadata[ $metadata_field_name ];
+			$processed_modules = array();
+			if ( is_array( $modules ) ) {
+				for ( $index = 0; $index < count( $modules ); $index++ ) {
+					$processed_modules[] = gutenberg_register_block_module_id(
+						$metadata,
+						$metadata_field_name,
+						$index
+					);
+				}
+			} else {
+				$processed_modules[] = gutenberg_register_block_module_id(
+					$metadata,
+					$metadata_field_name
+				);
+			}
+			$settings[ $settings_field_name ] = $processed_modules;
+		}
+	}
+
+	return $settings;
+}
+
+add_filter( 'block_type_metadata_settings', 'gutenberg_filter_block_type_metadata_settings_register_modules', 10, 2 );
+
+/**
+ * Enqueue modules associated with the block.
+ *
+ * @param string   $block_content The block content.
+ * @param array    $block         The full block, including name and attributes.
+ * @param WP_Block $instance      The block instance.
+ */
+function gutenberg_filter_render_block_enqueue_view_modules( $block_content, $parsed_block, $block_instance ) {
+	$block_type = $block_instance->block_type;
+
+	if ( ! empty( $block_type->view_module_ids ) ) {
+		foreach ( $block_type->view_module_ids as $module_id ) {
+			gutenberg_enqueue_module( $module_id );
+		}
+	}
+
+	return $block_content;
+}
+
+add_filter( 'render_block', 'gutenberg_filter_render_block_enqueue_view_modules', 10, 3 );
+
+/**
+ * Finds a module ID for the selected block metadata field. It detects
+ * when a path to file was provided and finds a corresponding asset file
+ * with details necessary to register the module under an automatically
+ * generated module ID.
+ *
+ * This is analogous to the `register_block_script_handle` in WordPress Core.
+ *
+ * @param array  $metadata   Block metadata.
+ * @param string $field_name Field name to pick from metadata.
+ * @param int    $index      Optional. Index of the script to register when multiple items passed.
+ *                           Default 0.
+ * @return string Module ID.
+ */
+function gutenberg_register_block_module_id( $metadata, $field_name, $index = 0 ) {
+	if ( empty( $metadata[ $field_name ] ) ) {
+		return false;
+	}
+
+	$module_id = $metadata[ $field_name ];
+	if ( is_array( $module_id ) ) {
+		if ( empty( $module_id[ $index ] ) ) {
+			return false;
+		}
+		$module_id = $module_id[ $index ];
+	}
+
+	$module_path = remove_block_asset_path_prefix( $module_id );
+	if ( $module_id === $module_path ) {
+		return $module_id;
+	}
+
+	$path                  = dirname( $metadata['file'] );
+	$module_asset_raw_path = $path . '/' . substr_replace( $module_path, '.asset.php', - strlen( '.js' ) );
+	$module_id             = gutenberg_generate_block_asset_module_id( $metadata['name'], $field_name, $index );
+	$module_asset_path     = wp_normalize_path( realpath( $module_asset_raw_path ) );
+
+	if ( empty( $module_asset_path ) ) {
+		_doing_it_wrong(
+			__FUNCTION__,
+			sprintf(
+				// This string is from WordPress Core. See `register_block_script_handle`.
+				// Translators: This is a translation from WordPress Core (default). No need to translate.
+				__( 'The asset file (%1$s) for the "%2$s" defined in "%3$s" block definition is missing.', 'default' ),
+				$module_asset_raw_path,
+				$field_name,
+				$metadata['name']
+			),
+			'6.5.0'
+		);
+		return false;
+	}
+
+	$module_path_norm    = wp_normalize_path( realpath( $path . '/' . $module_path ) );
+	$module_uri          = get_block_asset_url( $module_path_norm );
+	$module_asset        = require $module_asset_path;
+	$module_dependencies = isset( $module_asset['dependencies'] ) ? $module_asset['dependencies'] : array();
+
+	gutenberg_register_module(
+		$module_id,
+		$module_uri,
+		$module_dependencies,
+		isset( $module_asset['version'] ) ? $module_asset['version'] : false
+	);
+
+	return $module_id;
+}
+
+/**
+ * Generates the module ID for an asset based on the name of the block
+ * and the field name provided.
+ *
+ * This is analogous to the `generate_block_asset_handle` in WordPress Core.
+ *
+ * @param string $block_name Name of the block.
+ * @param string $field_name Name of the metadata field.
+ * @param int    $index      Optional. Index of the asset when multiple items passed.
+ *                           Default 0.
+ * @return string Generated module ID for the block's field.
+ */
+function gutenberg_generate_block_asset_module_id( $block_name, $field_name, $index = 0 ) {
+	if ( str_starts_with( $block_name, 'core/' ) ) {
+		$asset_handle = str_replace( 'core/', 'wp-block-', $block_name );
+		if ( str_starts_with( $field_name, 'editor' ) ) {
+			$asset_handle .= '-editor';
+		}
+		if ( str_starts_with( $field_name, 'view' ) ) {
+			$asset_handle .= '-view';
+		}
+		if ( $index > 0 ) {
+			$asset_handle .= '-' . ( $index + 1 );
+		}
+		return $asset_handle;
+	}
+
+	$field_mappings = array(
+		'viewModule' => 'view-module',
+	);
+	$asset_handle   = str_replace( '/', '-', $block_name ) .
+		'-' . $field_mappings[ $field_name ];
+	if ( $index > 0 ) {
+		$asset_handle .= '-' . ( $index + 1 );
+	}
+	return $asset_handle;
+}
+
+function gutenberg_register_view_module_ids_rest_field() {
+	register_rest_field(
+		'block-type',
+		'view_module_ids',
+		array(
+			'get_callback' => function ( $item ) {
+				 $block_type = WP_Block_Type_Registry::get_instance()->get_registered( $item['name'] );
+				if ( isset( $block_type->view_module_ids ) ) {
+					return $block_type->view_module_ids;
+				}
+				return array();
+			},
+		)
+	);
+}
+
+add_action( 'rest_api_init', 'gutenberg_register_view_module_ids_rest_field' );