File: //srv/wordpress/core/beta/wp-includes/blocks/gallery.php
<?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.
*
* @since 5.9.0
*
* @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' );
/**
* Adds a unique ID to the gallery block context.
*
* @since 7.0.0
*
* @param array $context Default context.
* @param array $parsed_block Block being rendered, filtered by render_block_data.
* @return array Filtered context.
*/
function block_core_gallery_render_context( $context, $parsed_block ) {
if ( 'core/gallery' === $parsed_block['blockName'] ) {
$context['galleryId'] = uniqid();
}
return $context;
}
add_filter( 'render_block_context', 'block_core_gallery_render_context', 10, 2 );
/**
* Returns the column gap value used for Gallery image width calculations.
*
* @since 7.1.0
*
* @param string|array|null $gap Gallery block gap value.
* @param string $fallback_gap Fallback gap value.
* @return string Gallery column gap value.
*/
function block_core_gallery_get_column_gap_value( $gap, $fallback_gap ) {
if ( is_array( $gap ) ) {
$gap = $gap['left'] ?? $fallback_gap;
}
// Make sure $gap is a string to avoid PHP 8.1 deprecation error in preg_match() when the value is null.
$gap = is_string( $gap ) ? $gap : '';
// Skip if gap value contains unsupported characters.
// Regex for CSS value borrowed from `safecss_filter_attr`, and used here
// because we only want to match against the value, not the CSS attribute.
$gap = $gap && preg_match( '%[\\\(&=}]|/\*%', $gap ) ? null : $gap;
// Get spacing CSS variable from preset value if provided.
if ( is_string( $gap ) && str_contains( $gap, 'var:preset|spacing|' ) ) {
$index_to_splice = strrpos( $gap, '|' ) + 1;
$slug = _wp_to_kebab_case( substr( $gap, $index_to_splice ) );
$gap = "var(--wp--preset--spacing--$slug)";
}
$gap_column = ( null !== $gap && '' !== $gap ) ? $gap : $fallback_gap;
// The unstable gallery gap calculation requires a real value (such as `0px`) and not `0`.
return '0' === $gap_column ? '0px' : $gap_column;
}
/**
* Resolves a Gallery block's `dynamicContent` to an ordered list of image
* attachment IDs.
*
* The `source` key is the dispatch discriminator and `args` holds the source's
* parameters. This `{ source, args }` shape mirrors the Block Bindings metadata
* shape so dynamic mode can migrate to an `innerBlocks` binding with minimal
* change. `core/attached-media` is a context-relative anchor (the post the gallery is
* rendered within); future sources translate their REST-named `args` (`author`,
* `categories`, `after`/`before`, `media_type`, etc.) into `WP_Query` arguments
* here.
*
* @since 7.0.0
*
* @param array $source The gallery's `dynamicContent` attribute.
* @param WP_Block $block The gallery block instance being rendered.
* @return int[] Ordered list of image attachment IDs.
*/
function block_core_gallery_resolve_dynamic_source( $source, $block ) {
if ( ! is_array( $source ) ) {
return array();
}
$source_name = $source['source'] ?? null;
$args = isset( $source['args'] ) && is_array( $source['args'] ) ? $source['args'] : array();
switch ( $source_name ) {
case 'core/attached-media':
// Prefer the post supplied via block context, falling back to the post
// being rendered. The fallback is what lets a post-bound template (e.g.
// `single`/`page`) resolve against the actual post at render time even
// though the editor has no concrete post to preview — the editor gates
// the dynamic-mode UI on that same context (see `use-dynamic-gallery.js`).
$post_id = $block->context['postId'] ?? get_the_ID();
if ( ! $post_id ) {
return array();
}
// Map the camelCase `args` (block-attribute convention) to WP_Query
// names, defaulting to the same order as the editor preview (see
// `dynamic-source.js`). Only REST-supported orderby values are
// allowed; `menu_order` is intentionally unsupported (it isn't a
// valid media REST `orderby`).
$orderby = $args['orderBy'] ?? 'date';
if ( ! in_array( $orderby, array( 'date', 'title' ), true ) ) {
$orderby = 'date';
}
$order = strtoupper( $args['order'] ?? 'desc' ) === 'ASC' ? 'ASC' : 'DESC';
// Bound the number of resolved images until the gallery supports
// pagination. Kept in sync with the editor query's `per_page` cap; a
// case-insensitive grep for `max_images` finds both this and
// `MAX_IMAGES` in `dynamic-source.js`.
$max_images = 100;
$query = new WP_Query(
array(
'post_parent' => $post_id,
'post_type' => 'attachment',
'post_status' => 'inherit',
'post_mime_type' => 'image',
'orderby' => $orderby,
'order' => $order,
'posts_per_page' => $max_images,
'fields' => 'ids',
'no_found_rows' => true,
)
);
return array_map( 'intval', $query->posts );
}
// Unknown or not-yet-implemented source type.
return array();
}
/**
* Builds the link-related image block attributes for a dynamically rendered
* gallery image, mapping the gallery-wide `linkTo` setting onto a single image.
*
* Mirrors the editor's `getHrefAndDestination()` (see `gallery/utils.js`).
*
* @since 7.0.0
*
* @param int $attachment_id The image attachment ID.
* @param array $attributes The gallery block attributes.
* @return array Partial image block attributes (`href`, `linkDestination`,
* `linkTarget`, `rel`, `lightbox`).
*/
function block_core_gallery_dynamic_image_link_attributes( $attachment_id, $attributes ) {
$link_to = $attributes['linkTo'] ?? 'none';
$attrs = array();
switch ( $link_to ) {
// Gutenberg uses 'media'/'attachment'; WP Core uses 'file'/'post'.
case 'media':
case 'file':
$attrs['href'] = wp_get_attachment_url( $attachment_id );
$attrs['linkDestination'] = 'media';
break;
case 'attachment':
case 'post':
$attrs['href'] = get_attachment_link( $attachment_id );
$attrs['linkDestination'] = 'attachment';
break;
case 'lightbox':
$attrs['linkDestination'] = 'none';
$attrs['lightbox'] = array( 'enabled' => true );
break;
}
if ( ! empty( $attrs['href'] ) && '_blank' === ( $attributes['linkTarget'] ?? '' ) ) {
$attrs['linkTarget'] = '_blank';
$attrs['rel'] = 'noopener';
}
return $attrs;
}
/**
* Renders a single `core/image` block for a Gallery block running in dynamic
* mode, applying the gallery-wide settings that affect how an image renders.
*
* The image markup is generated here (via `wp_get_attachment_image()`) and
* rendered through a real `core/image` block instance so that the image block's
* own render callback and lightbox behavior run, and so the gallery's existing
* lightbox/interactivity post-processing can pick it up.
*
* @since 7.0.0
*
* @param int $attachment_id The image attachment ID.
* @param array $attributes The gallery block attributes.
* @param array $context Context to expose to the inner image block.
* @return string The rendered image block HTML, or an empty string on failure.
*/
function block_core_gallery_render_dynamic_image( $attachment_id, $attributes, $context ) {
$size_slug = $attributes['sizeSlug'] ?? 'large';
$aspect_ratio = $attributes['aspectRatio'] ?? 'auto';
$img_attr = array( 'class' => 'wp-image-' . $attachment_id );
if ( $aspect_ratio && 'auto' !== $aspect_ratio ) {
// Run the aspect ratio through the same sanitization used for every other
// block inline style, so an unsafe value can't break out of the style
// attribute or inject additional markup.
$img_attr['style'] = safecss_filter_attr(
sprintf( 'aspect-ratio:%s;object-fit:cover;', $aspect_ratio )
);
}
$image_markup = wp_get_attachment_image( $attachment_id, $size_slug, false, $img_attr );
if ( ! $image_markup ) {
return '';
}
$image_attributes = array_merge(
array(
'id' => $attachment_id,
'data-id' => (string) $attachment_id,
'sizeSlug' => $size_slug,
),
block_core_gallery_dynamic_image_link_attributes( $attachment_id, $attributes )
);
if ( $aspect_ratio && 'auto' !== $aspect_ratio ) {
$image_attributes['aspectRatio'] = $aspect_ratio;
$image_attributes['scale'] = 'cover';
}
// Wrap in a link when the gallery links images somewhere.
if ( ! empty( $image_attributes['href'] ) ) {
$image_markup = sprintf(
'<a href="%1$s"%2$s%3$s>%4$s</a>',
esc_url( $image_attributes['href'] ),
isset( $image_attributes['linkTarget'] ) ? ' target="' . esc_attr( $image_attributes['linkTarget'] ) . '"' : '',
isset( $image_attributes['rel'] ) ? ' rel="' . esc_attr( $image_attributes['rel'] ) . '"' : '',
$image_markup
);
}
// Use the raw caption (`post_excerpt`) so the frontend mirrors the editor
// preview, which builds the caption from the REST `caption.raw` value. Gap:
// the REST API exposes no caption run through `wp_get_attachment_caption`, so
// that filter isn't applied here either.
$attachment = get_post( $attachment_id );
$caption = $attachment ? $attachment->post_excerpt : '';
if ( '' !== $caption ) {
$image_markup .= sprintf(
'<figcaption class="wp-element-caption">%s</figcaption>',
wp_kses_post( $caption )
);
}
$figure = sprintf(
'<figure class="wp-block-image size-%1$s">%2$s</figure>',
esc_attr( $size_slug ),
$image_markup
);
$image_block = array(
'blockName' => 'core/image',
'attrs' => $image_attributes,
'innerBlocks' => array(),
'innerHTML' => $figure,
'innerContent' => array( $figure ),
);
return ( new WP_Block( $image_block, $context ) )->render();
}
/**
* Renders the `core/gallery` block on the server.
*
* @since 6.0.0
*
* @param array $attributes Attributes of the block being rendered.
* @param string $content Content of the block being rendered.
* @param array $block The block instance being rendered.
* @return string The content of the block being rendered.
*/
function block_core_gallery_render( $attributes, $content, $block ) {
static $global_styles = null;
// In dynamic mode the gallery's images are resolved at render time instead of
// being authored as inner blocks, so `save.js` persists at most the
// gallery-level caption — a bare `<figcaption>`, or nothing when there is no
// caption. Resolve the configured source to a list of attachments, render an
// image block for each, and build the gallery `<figure>` wrapper from scratch.
// The gap/randomOrder/lightbox post-processing below then runs over the
// constructed markup unchanged.
if ( ! empty( $attributes['dynamicContent'] ) ) {
$attachment_ids = block_core_gallery_resolve_dynamic_source( $attributes['dynamicContent'], $block );
// Nothing resolved — no attachments, or an unrecognized source. Render
// nothing rather than an empty gallery wrapper; a saved caption is
// meaningless without images, so it is intentionally dropped too.
if ( empty( $attachment_ids ) ) {
return '';
}
// The source query only fetched IDs (`fields => ids`), which skips
// WP_Query's cache priming. Each image rendered below reads the
// attachment post and its meta (via `wp_get_attachment_image()`,
// `get_post()`, etc.), so warm the post and meta caches in a single pair
// of queries up front instead of paying ~two queries per attachment.
// Term cache is left cold: the render path doesn't read attachment terms.
if ( count( $attachment_ids ) > 1 ) {
_prime_post_caches( $attachment_ids, false, true );
}
// Expose the gallery's provided context (plus galleryId/postId/postType)
// to each image block, since these images are rendered outside the
// gallery's real inner-block tree.
$image_context = array_merge(
is_array( $block->context ) ? $block->context : array(),
array(
'allowResize' => $attributes['allowResize'] ?? false,
'imageCrop' => $attributes['imageCrop'] ?? true,
'fixedHeight' => $attributes['fixedHeight'] ?? true,
'navigationButtonType' => $attributes['navigationButtonType'] ?? 'icon',
)
);
$images_markup = '';
foreach ( $attachment_ids as $attachment_id ) {
$images_markup .= block_core_gallery_render_dynamic_image( $attachment_id, $attributes, $image_context );
}
// Build the wrapper rather than parsing/splicing saved markup.
// `get_block_wrapper_attributes()` supplies the block-support
// classes/styles (align, color, border, spacing, anchor id); the layout
// render filter adds the flex layout classes downstream — the same way a
// static gallery's wrapper is composed (`useBlockProps.save()` plus that
// filter). Only the gallery-specific classes are added explicitly, and
// they mirror `save.js` (kept in sync deliberately — see that file).
$gallery_classes = 'wp-block-gallery has-nested-images';
$gallery_classes .= isset( $attributes['columns'] )
? ' columns-' . (int) $attributes['columns']
: ' columns-default';
if ( $attributes['imageCrop'] ?? true ) {
$gallery_classes .= ' is-cropped';
}
$wrapper_attributes = get_block_wrapper_attributes( array( 'class' => $gallery_classes ) );
// In dynamic mode `save.js` persists only the gallery-level caption, so
// `$content` is the saved `<figcaption>` (or empty). Append it after the
// resolved images — matching the static gallery's `{images}{caption}`
// order — without parsing it.
$content = sprintf( '<figure %s>%s%s</figure>', $wrapper_attributes, $images_markup, $content );
}
// Adds a style tag for the --wp--style--unstable-gallery-gap var.
// The Gallery block needs to recalculate Image block width based on
// the current gap setting in order to maintain the number of flex columns
// so a css var is added to allow this.
$style_attr = is_array( $attributes['style'] ?? null )
? $attributes['style']
: array();
if (
defined( 'IS_GUTENBERG_PLUGIN' ) &&
IS_GUTENBERG_PLUGIN &&
function_exists( 'gutenberg_resolve_style_state_aliases' )
) {
$style_attr = gutenberg_resolve_style_state_aliases( $style_attr, 'core/gallery' );
}
$unique_gallery_classname = wp_unique_id( 'wp-block-gallery-' );
$processed_content = new WP_HTML_Tag_Processor( $content );
$processed_content->next_tag();
$processed_content->add_class( $unique_gallery_classname );
// --gallery-block--gutter-size is deprecated. --wp--style--gallery-gap-default should be used by themes that want to set a default
// gap on the gallery.
$fallback_gap = 'var( --wp--style--gallery-gap-default, var( --gallery-block--gutter-size, var( --wp--style--block-gap, 0.5em ) ) )';
if ( null === $global_styles ) {
$global_styles = function_exists( 'wp_get_global_styles' ) ? wp_get_global_styles() : array();
}
$global_gallery_styles = $global_styles['blocks']['core/gallery'] ?? array();
$global_gallery_gap = $global_gallery_styles['spacing']['blockGap'] ?? $fallback_gap;
$has_block_gap = is_array( $style_attr['spacing'] ?? null ) && array_key_exists( 'blockGap', $style_attr['spacing'] );
// Prefer the block's own gap value, then Gallery global styles. Missing
// values fall back to the Gallery blockGap default.
$block_gap = $has_block_gap
? $style_attr['spacing']['blockGap']
: $global_gallery_gap;
$gap_column = block_core_gallery_get_column_gap_value( $block_gap, $fallback_gap );
// Set the CSS variable to the column value for Gallery's flex width calculations.
$gallery_styles = array(
array(
'selector' => ".wp-block-gallery.{$unique_gallery_classname}",
'declarations' => array(
'--wp--style--unstable-gallery-gap' => $gap_column,
),
),
);
$global_settings = wp_get_global_settings();
$viewport_settings = $global_settings['viewport'] ?? null;
$responsive_media_queries = array();
foreach ( array( 'WP_Theme_JSON_Gutenberg', 'WP_Theme_JSON' ) as $theme_json_class_name ) {
if ( method_exists( $theme_json_class_name, 'get_viewport_media_queries' ) ) {
$responsive_media_queries = $theme_json_class_name::get_viewport_media_queries( $viewport_settings );
break;
}
}
foreach ( $responsive_media_queries as $breakpoint => $media_query ) {
$viewport_style = $style_attr[ $breakpoint ] ?? null;
$has_viewport_block_gap = is_array( $viewport_style ) &&
is_array( $viewport_style['spacing'] ?? null ) &&
array_key_exists( 'blockGap', $viewport_style['spacing'] );
$has_global_viewport_block_gap = is_array( $global_gallery_styles[ $breakpoint ]['spacing'] ?? null ) &&
array_key_exists( 'blockGap', $global_gallery_styles[ $breakpoint ]['spacing'] );
// Viewport-specific block values win. Gallery global viewport values
// only apply when the block has no base gap, so they do not override an instance value.
if ( $has_viewport_block_gap ) {
$viewport_gap = $viewport_style['spacing']['blockGap'];
} elseif ( ! $has_block_gap && $has_global_viewport_block_gap ) {
$viewport_gap = $global_gallery_styles[ $breakpoint ]['spacing']['blockGap'];
} else {
continue;
}
if ( null === $viewport_gap ) {
continue;
}
$gallery_styles[] = array(
'selector' => ".wp-block-gallery.{$unique_gallery_classname}",
'declarations' => array(
'--wp--style--unstable-gallery-gap' => block_core_gallery_get_column_gap_value(
$viewport_gap,
$fallback_gap
),
),
'rules_group' => $media_query,
);
}
wp_style_engine_get_stylesheet_from_css_rules(
$gallery_styles,
array( 'context' => 'block-supports' )
);
// The WP_HTML_Tag_Processor class calls get_updated_html() internally
// when the instance is treated as a string, but here we explicitly
// convert it to a string.
$updated_content = $processed_content->get_updated_html();
/*
* Randomize the order of image blocks. Ideally we should shuffle
* the `$parsed_block['innerBlocks']` via the `render_block_data` hook.
* However, this hook doesn't apply inner block updates when blocks are
* nested.
* @todo In the future, if this hook supports updating innerBlocks in
* nested blocks, it should be refactored.
*
* @see: https://github.com/WordPress/gutenberg/pull/58733
*/
if ( ! empty( $attributes['randomOrder'] ) ) {
// This pattern matches figure elements with the `wp-block-image`
// class to avoid the gallery's wrapping `figure` element and
// extract images only.
$pattern = '/<figure[^>]*\bwp-block-image\b[^>]*>.*?<\/figure>/s';
preg_match_all( $pattern, $updated_content, $matches );
if ( $matches ) {
$image_blocks = $matches[0];
shuffle( $image_blocks );
$i = 0;
$updated_content = preg_replace_callback(
$pattern,
static function () use ( $image_blocks, &$i ) {
return $image_blocks[ $i++ ];
},
$updated_content
);
}
}
// Gets all image IDs from the state that match this gallery's ID.
$state = wp_interactivity_state( 'core/image' );
$gallery_id = $block->context['galleryId'] ?? null;
$image_ids = array();
// Extracts image IDs from state metadata that match the current gallery ID.
if ( isset( $gallery_id ) && isset( $state['metadata'] ) ) {
foreach ( $state['metadata'] as $image_id => $metadata ) {
if ( isset( $metadata['galleryId'] ) && $metadata['galleryId'] === $gallery_id ) {
$image_ids[] = $image_id;
}
}
}
// If there are image IDs associated with this gallery, set interactivity
// attributes and order metadata for lightbox navigation.
if ( ! empty( $image_ids ) ) {
$total = count( $image_ids );
$lightbox_index = 0;
$processor = new WP_HTML_Tag_Processor( $updated_content );
$processor->next_tag();
$processor->set_attribute( 'data-wp-interactive', 'core/gallery' );
$processor->set_attribute(
'data-wp-context',
wp_json_encode(
array( 'galleryId' => $gallery_id ),
JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_QUOT | JSON_HEX_AMP
)
);
while ( $processor->next_tag( 'figure' ) ) {
$wp_key = $processor->get_attribute( 'data-wp-key' );
if ( $wp_key && isset( $state['metadata'][ $wp_key ] ) ) {
$alt = $state['metadata'][ $wp_key ]['alt'];
wp_interactivity_state(
'core/image',
array(
'metadata' => array(
$wp_key => array(
'customAriaLabel' => empty( $alt )
/* translators: %1$s: current image index, %2$s: total number of images */
? sprintf( __( 'Enlarged image %1$s of %2$s' ), $lightbox_index + 1, $total )
/* translators: %1$s: current image index, %2$s: total number of images, %3$s: Image alt text */
: sprintf( __( 'Enlarged image %1$s of %2$s: %3$s' ), $lightbox_index + 1, $total, $alt ),
/* translators: %1$s: current image index, %2$s: total number of images */
'triggerButtonAriaLabel' => sprintf( __( 'Enlarge %1$s of %2$s' ), $lightbox_index + 1, $total ),
'order' => $lightbox_index,
),
),
)
);
++$lightbox_index;
}
}
return $processor->get_updated_html();
}
return $updated_content;
}
/**
* Registers the `core/gallery` block on server.
*
* @since 5.9.0
*/
function register_block_core_gallery() {
register_block_type_from_metadata(
__DIR__ . '/gallery',
array(
'render_callback' => 'block_core_gallery_render',
)
);
}
add_action( 'init', 'register_block_core_gallery' );