init

wp-includes/blocks/gallery.php

@@ -0,0 +1,51 @@
+<?php
+/**
+ * Server-side rendering of the `core/gallery` block.
+ *
+ * @package WordPress
+ */
+
+/**
+ * Handles backwards compatibility for Gallery Blocks,
+ * whose images feature a `data-id` attribute.
+ *
+ * Now that the Gallery Block contains inner Image Blocks,
+ * we add a custom `data-id` attribute before rendering the gallery
+ * so that the Image Block can pick it up in its render_callback.
+ *
+ * @param array $parsed_block The block being rendered.
+ * @return array The migrated block object.
+ */
+function block_core_gallery_data_id_backcompatibility( $parsed_block ) {
+	if ( 'core/gallery' === $parsed_block['blockName'] ) {
+		foreach ( $parsed_block['innerBlocks'] as $key => $inner_block ) {
+			if ( 'core/image' === $inner_block['blockName'] ) {
+				if ( ! isset( $parsed_block['innerBlocks'][ $key ]['attrs']['data-id'] ) && isset( $inner_block['attrs']['id'] ) ) {
+					$parsed_block['innerBlocks'][ $key ]['attrs']['data-id'] = esc_attr( $inner_block['attrs']['id'] );
+				}
+			}
+		}
+	}
+
+	return $parsed_block;
+}
+
+add_filter( 'render_block_data', 'block_core_gallery_data_id_backcompatibility' );
+
+/**
+ * Registers the `core/gallery` block on server.
+ * This render callback needs to be here
+ * so that the gallery styles are loaded in block-based themes.
+ */
+function register_block_core_gallery() {
+	register_block_type_from_metadata(
+		__DIR__ . '/gallery',
+		array(
+			'render_callback' => function ( $attributes, $content ) {
+				return $content;
+			},
+		)
+	);
+}
+
+add_action( 'init', 'register_block_core_gallery' );