<?php
/**
* Server-side rendering of the `core/breadcrumbs` block.
*
* @package WordPress
*/
/**
* Renders the `core/breadcrumbs` block on the server.
*
* @since 7.0.0
*
* @param array $attributes Block attributes.
* @param string $content Block default content.
* @param WP_Block $block Block instance.
*
* @return string Returns the post breadcrumb for hierarchical post types.
*/
function render_block_core_breadcrumbs( $attributes, $content, $block ) {
$is_front_page = is_front_page();
if ( ! $attributes['showOnHomePage'] && $is_front_page ) {
return '';
}
$is_home = is_home();
$page_for_posts = get_option( 'page_for_posts' );
$breadcrumb_items = array();
if ( $attributes['showHomeItem'] ) {
// We make `home` a link if not on front page, or if front page
// is set to a custom page and is paged.
if ( ! $is_front_page || ( 'page' === get_option( 'show_on_front' ) && (int) get_query_var( 'page' ) > 1 ) ) {
$breadcrumb_items[] = array(
'label' => __( 'Home' ),
'url' => home_url( '/' ),
);
} else {
$breadcrumb_items[] = block_core_breadcrumbs_create_item( __( 'Home' ), block_core_breadcrumbs_is_paged() );
}
}
// Handle home.
if ( $is_home ) {
// These checks are explicitly nested in order not to execute the `else` branch.
if ( $page_for_posts ) {
$breadcrumb_items[] = block_core_breadcrumbs_create_item( block_core_breadcrumbs_get_post_title( $page_for_posts ), block_core_breadcrumbs_is_paged() );
}
if ( block_core_breadcrumbs_is_paged() ) {
$breadcrumb_items[] = block_core_breadcrumbs_create_page_number_item();
}
} elseif ( $is_front_page ) {
// Handle front page.
// This check is explicitly nested in order not to execute the `else` branch.
// If front page is set to custom page and is paged, add the page number.
if ( (int) get_query_var( 'page' ) > 1 ) {
$breadcrumb_items[] = block_core_breadcrumbs_create_page_number_item( 'page' );
}
} elseif ( is_search() ) {
// Handle search results.
$is_paged = block_core_breadcrumbs_is_paged();
/* translators: %s: search query */
$text = sprintf( __( 'Search results for: "%s"' ), wp_trim_words( get_search_query(), 10 ) );
$breadcrumb_items[] = block_core_breadcrumbs_create_item( $text, $is_paged );
// Add the "Page X" as the current page if paginated.
if ( $is_paged ) {
$breadcrumb_items[] = block_core_breadcrumbs_create_page_number_item();
}
} elseif ( is_404() ) {
// Handle 404 pages.
$breadcrumb_items[] = array(
'label' => __( 'Page not found' ),
);
} elseif ( is_archive() ) {
// Handle archive pages (taxonomy, post type, date, author archives).
$archive_breadcrumbs = block_core_breadcrumbs_get_archive_breadcrumbs();
if ( ! empty( $archive_breadcrumbs ) ) {
$breadcrumb_items = array_merge( $breadcrumb_items, $archive_breadcrumbs );
}
} else {
// Handle single post/page breadcrumbs.
if ( ! isset( $block->context['postId'] ) || ! isset( $block->context['postType'] ) ) {
return '';
}
$post_id = $block->context['postId'];
$post_type = $block->context['postType'];
$post = get_post( $post_id );
if ( ! $post ) {
return '';
}
// For non-hierarchical post types with parents (e.g., attachments), build trail for the parent.
$post_parent = $post->post_parent;
$parent_post = null;
if ( ! is_post_type_hierarchical( $post_type ) && $post_parent ) {
$parent_post = get_post( $post_parent );
if ( $parent_post ) {
$post_id = $parent_post->ID;
$post_type = $parent_post->post_type;
$post_parent = $parent_post->post_parent;
}
}
// Determine breadcrumb type.
// Some non-hierarchical post types (e.g., attachments) can have parents.
// Use hierarchical breadcrumbs if a parent exists, otherwise use taxonomy breadcrumbs.
$show_terms = false;
if ( ! is_post_type_hierarchical( $post_type ) && ! $post_parent ) {
$show_terms = true;
} elseif ( empty( get_object_taxonomies( $post_type, 'objects' ) ) ) {
$show_terms = false;
} else {
$show_terms = $attributes['prefersTaxonomy'];
}
// Add post type archive link if applicable.
$post_type_object = get_post_type_object( $post_type );
$archive_link = get_post_type_archive_link( $post_type );
if ( $archive_link && untrailingslashit( home_url() ) !== untrailingslashit( $archive_link ) ) {
$label = $post_type_object->labels->archives;
if ( 'post' === $post_type && $page_for_posts ) {
$label = block_core_breadcrumbs_get_post_title( $page_for_posts );
}
$breadcrumb_items[] = array(
'label' => $label,
'url' => $archive_link,
);
}
// Build breadcrumb trail based on hierarchical structure or taxonomy terms.
if ( ! $show_terms ) {
$breadcrumb_items = array_merge( $breadcrumb_items, block_core_breadcrumbs_get_hierarchical_post_type_breadcrumbs( $post_id ) );
} else {
$breadcrumb_items = array_merge( $breadcrumb_items, block_core_breadcrumbs_get_terms_breadcrumbs( $post_id, $post_type ) );
}
// Add post title: linked when viewing a paginated page, plain text otherwise.
$is_paged = (int) get_query_var( 'page' ) > 1 || (int) get_query_var( 'cpage' ) > 1;
$title = block_core_breadcrumbs_get_post_title( $post );
if ( $is_paged ) {
$breadcrumb_items[] = array(
'label' => $title,
'url' => get_permalink( $post ),
'allow_html' => true,
);
$breadcrumb_items[] = block_core_breadcrumbs_create_page_number_item( (int) get_query_var( 'cpage' ) > 1 ? 'cpage' : 'page' );
} else {
$breadcrumb_items[] = array(
'label' => $title,
'allow_html' => true,
);
}
}
// Remove current item if disabled.
if ( ! $attributes['showCurrentItem'] && ! empty( $breadcrumb_items ) ) {
array_pop( $breadcrumb_items );
}
/**
* Filters the breadcrumb items array before rendering.
*
* Allows developers to modify, add, or remove breadcrumb items.
*
* @since 7.0.0
*
* @param array[] $breadcrumb_items {
* Array of breadcrumb item data.
*
* @type string $label The breadcrumb text.
* @type string $url Optional. The breadcrumb link URL.
* @type bool $allow_html Optional. Whether to allow HTML in the label.
* When true, the label will be sanitized with wp_kses_post(),
* allowing only safe HTML tags. When false or omitted, all HTML
* will be escaped with esc_html(). Default false.
* }
*/
$breadcrumb_items = apply_filters( 'block_core_breadcrumbs_items', $breadcrumb_items );
if ( empty( $breadcrumb_items ) ) {
return '';
}
$wrapper_attributes = get_block_wrapper_attributes(
array(
'style' => '--separator: "' . addcslashes( $attributes['separator'], '\\"' ) . '";',
'aria-label' => __( 'Breadcrumbs' ),
)
);
$breadcrumb_html = sprintf(
'<nav %s><ol>%s</ol></nav>',
$wrapper_attributes,
implode(
'',
array_map(
static function ( $item ) {
$label = ! empty( $item['allow_html'] ) ? wp_kses_post( $item['label'] ) : esc_html( $item['label'] );
if ( ! empty( $item['url'] ) ) {
return '<li><a href="' . esc_url( $item['url'] ) . '">' . $label . '</a></li>';
}
return '<li><span aria-current="page">' . $label . '</span></li>';
},
$breadcrumb_items
)
)
);
return $breadcrumb_html;
}
/**
* Checks if we're on a paginated view (page 2 or higher).
*
* @since 7.0.0
*
* @return bool True if paged > 1, false otherwise.
*/
function block_core_breadcrumbs_is_paged() {
$paged = (int) get_query_var( 'paged' );
return $paged > 1;
}
/**
* Creates a "Page X" breadcrumb item for paginated views.
*
* @since 7.0.0
* @param string $query_var Optional. Query variable to get current page number. Default 'paged'.
* @return array The "Page X" breadcrumb item data.
*/
function block_core_breadcrumbs_create_page_number_item( $query_var = 'paged' ) {
$paged = (int) get_query_var( $query_var );
if ( 'cpage' === $query_var ) {
return array(
'label' => sprintf(
/* translators: %s: comment page number */
__( 'Comments Page %s' ),
number_format_i18n( $paged )
),
);
}
return array(
'label' => sprintf(
/* translators: %s: page number */
__( 'Page %s' ),
number_format_i18n( $paged )
),
);
}
/**
* Creates a breadcrumb item that's either a link or current page item.
*
* When paginated (is_paged is true), creates a link to page 1.
* Otherwise, creates a span marked as the current page.
*
* @since 7.0.0
*
* @param string $text The text content.
* @param bool $is_paged Whether we're on a paginated view.
*
* @return array The breadcrumb item data.
*/
function block_core_breadcrumbs_create_item( $text, $is_paged = false ) {
$item = array( 'label' => $text );
if ( $is_paged ) {
$item['url'] = get_pagenum_link( 1 );
}
return $item;
}
/**
* Gets a post title with fallback for empty titles.
*
* @since 7.0.0
*
* @param int|WP_Post $post_id_or_object The post ID or post object.
*
* @return string The post title or fallback text.
*/
function block_core_breadcrumbs_get_post_title( $post_id_or_object ) {
$title = get_the_title( $post_id_or_object );
if ( strlen( $title ) === 0 ) {
$title = __( '(no title)' );
}
return $title;
}
/**
* Generates breadcrumb items from hierarchical post type ancestors.
*
* @since 7.0.0
*
* @param int $post_id The post ID.
*
* @return array Array of breadcrumb item data.
*/
function block_core_breadcrumbs_get_hierarchical_post_type_breadcrumbs( $post_id ) {
$breadcrumb_items = array();
$ancestors = get_post_ancestors( $post_id );
$ancestors = array_reverse( $ancestors );
foreach ( $ancestors as $ancestor_id ) {
$breadcrumb_items[] = array(
'label' => block_core_breadcrumbs_get_post_title( $ancestor_id ),
'url' => get_permalink( $ancestor_id ),
'allow_html' => true,
);
}
return $breadcrumb_items;
}
/**
* Generates breadcrumb items for hierarchical term ancestors.
*
* For hierarchical taxonomies, retrieves and formats ancestor terms as breadcrumb links.
*
* @since 7.0.0
*
* @param int $term_id The term ID.
* @param string $taxonomy The taxonomy name.
*
* @return array Array of breadcrumb item data for ancestors.
*/
function block_core_breadcrumbs_get_term_ancestors_items( $term_id, $taxonomy ) {
$breadcrumb_items = array();
// Check if taxonomy is hierarchical and add ancestor term links.
if ( is_taxonomy_hierarchical( $taxonomy ) ) {
$term_ancestors = get_ancestors( $term_id, $taxonomy, 'taxonomy' );
$term_ancestors = array_reverse( $term_ancestors );
foreach ( $term_ancestors as $ancestor_id ) {
$ancestor_term = get_term( $ancestor_id, $taxonomy );
if ( $ancestor_term && ! is_wp_error( $ancestor_term ) ) {
$breadcrumb_items[] = array(
'label' => $ancestor_term->name,
'url' => get_term_link( $ancestor_term ),
);
}
}
}
return $breadcrumb_items;
}
/**
* Generates breadcrumb items for archive pages.
*
* Handles taxonomy archives, post type archives, date archives, and author archives.
* For hierarchical taxonomies, includes ancestor terms in the breadcrumb trail.
*
* @since 7.0.0
*
* @return array Array of breadcrumb item data.
*/
function block_core_breadcrumbs_get_archive_breadcrumbs() {
$breadcrumb_items = array();
// Date archive (check first since it doesn't have a queried object).
if ( is_date() ) {
$year = get_query_var( 'year' );
$month = get_query_var( 'monthnum' );
$day = get_query_var( 'day' );
// Fallback to 'm' query var for plain permalinks.
// Plain permalinks use ?m=YYYYMMDD format instead of separate query vars.
if ( ! $year ) {
$m = get_query_var( 'm' );
if ( $m ) {
$year = substr( $m, 0, 4 );
$month = substr( $m, 4, 2 );
$day = (int) substr( $m, 6, 2 );
}
}
$is_paged = block_core_breadcrumbs_is_paged();
if ( $year ) {
if ( $month ) {
// Year is linked if we have month.
$breadcrumb_items[] = array(
'label' => $year,
'url' => get_year_link( $year ),
);
if ( $day ) {
// Month is linked if we have day.
$breadcrumb_items[] = array(
'label' => date_i18n( 'F', mktime( 0, 0, 0, $month, 1, $year ) ),
'url' => get_month_link( $year, $month ),
);
// Add day (current if not paginated, link if paginated).
$breadcrumb_items[] = block_core_breadcrumbs_create_item(
$day,
$is_paged
);
} else {
// Add month (current if not paginated, link if paginated).
$breadcrumb_items[] = block_core_breadcrumbs_create_item(
date_i18n( 'F', mktime( 0, 0, 0, $month, 1, $year ) ),
$is_paged
);
}
} else {
// Add year (current if not paginated, link if paginated).
$breadcrumb_items[] = block_core_breadcrumbs_create_item(
$year,
$is_paged
);
}
}
// Add pagination breadcrumb if on a paged date archive.
if ( $is_paged ) {
$breadcrumb_items[] = block_core_breadcrumbs_create_page_number_item();
}
return $breadcrumb_items;
}
// For other archive types, we need a queried object.
$queried_object = get_queried_object();
if ( ! $queried_object ) {
return array();
}
$is_paged = block_core_breadcrumbs_is_paged();
// Taxonomy archive (category, tag, custom taxonomy).
if ( $queried_object instanceof WP_Term ) {
$term = $queried_object;
$taxonomy = $term->taxonomy;
// Add hierarchical term ancestors if applicable.
$breadcrumb_items = array_merge(
$breadcrumb_items,
block_core_breadcrumbs_get_term_ancestors_items( $term->term_id, $taxonomy )
);
// Add current term (current if not paginated, link if paginated).
$breadcrumb_items[] = block_core_breadcrumbs_create_item(
$term->name,
$is_paged
);
} elseif ( is_post_type_archive() ) {
// Post type archive.
$post_type = get_query_var( 'post_type' );
if ( is_array( $post_type ) ) {
$post_type = reset( $post_type );
}
$post_type_object = get_post_type_object( $post_type );
/** This filter is documented in wp-includes/general-template.php */
$title = apply_filters( 'post_type_archive_title', $post_type_object->labels->archives, $post_type ); // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals.NonPrefixedHooknameFound
if ( $post_type_object ) {
// Add post type (current if not paginated, link if paginated).
$breadcrumb_items[] = block_core_breadcrumbs_create_item(
$title ? $title : $post_type_object->labels->archives,
$is_paged
);
}
} elseif ( is_author() ) {
// Author archive.
$author = $queried_object;
// Add author (current if not paginated, link if paginated).
$breadcrumb_items[] = block_core_breadcrumbs_create_item(
$author->display_name,
$is_paged
);
}
// Add pagination breadcrumb if on a paged archive.
if ( $is_paged ) {
$breadcrumb_items[] = block_core_breadcrumbs_create_page_number_item();
}
return $breadcrumb_items;
}
/**
* Generates breadcrumb items from taxonomy terms.
*
* Finds the first publicly queryable taxonomy with terms assigned to the post
* and generates breadcrumb links, including hierarchical term ancestors if applicable.
*
* @since 7.0.0
*
* @param int $post_id The post ID.
* @param string $post_type The post type name.
*
* @return array Array of breadcrumb item data.
*/
function block_core_breadcrumbs_get_terms_breadcrumbs( $post_id, $post_type ) {
$breadcrumb_items = array();
// Get public taxonomies for this post type.
$taxonomies = wp_filter_object_list(
get_object_taxonomies( $post_type, 'objects' ),
array(
'publicly_queryable' => true,
'show_in_rest' => true,
)
);
if ( empty( $taxonomies ) ) {
return $breadcrumb_items;
}
/**
* Filters breadcrumb settings (taxonomy and term selection) for a post or post type.
*
* Allows developers to specify which taxonomy and term should be used in the
* breadcrumb trail when a post type has multiple taxonomies or when a post is
* assigned to multiple terms within a taxonomy.
*
* @since 7.0.0
*
* @param array $settings {
* Array of breadcrumb settings. Default empty array.
*
* @type string $taxonomy Optional. Taxonomy slug to use for breadcrumbs.
* The taxonomy must be registered for the post type and have
* terms assigned to the post. If not found or has no terms,
* fall back to the first available taxonomy with terms.
* @type string $term Optional. Term slug to use when the post has multiple terms
* in the selected taxonomy. If the term is not found or not
* assigned to the post, fall back to the first term. If the
* post has only one term, that term is used regardless.
* }
* @param string $post_type The post type slug.
* @param int $post_id The post ID.
*/
$settings = apply_filters( 'block_core_breadcrumbs_post_type_settings', array(), $post_type, $post_id );
$taxonomy_name = null;
$terms = array();
// Try preferred taxonomy first if specified.
if ( ! empty( $settings['taxonomy'] ) ) {
foreach ( $taxonomies as $taxonomy ) {
if ( $taxonomy->name === $settings['taxonomy'] ) {
$post_terms = get_the_terms( $post_id, $taxonomy->name );
if ( ! empty( $post_terms ) && ! is_wp_error( $post_terms ) ) {
$taxonomy_name = $taxonomy->name;
$terms = $post_terms;
}
break;
}
}
}
// If no preferred taxonomy or it didn't have terms, find the first taxonomy with terms.
if ( empty( $terms ) ) {
foreach ( $taxonomies as $taxonomy ) {
$post_terms = get_the_terms( $post_id, $taxonomy->name );
if ( ! empty( $post_terms ) && ! is_wp_error( $post_terms ) ) {
$taxonomy_name = $taxonomy->name;
$terms = $post_terms;
break;
}
}
}
if ( ! empty( $terms ) ) {
// Select which term to use.
$term = reset( $terms );
// Try preferred term if specified and post has multiple terms.
if ( ! empty( $settings['term'] ) && count( $terms ) > 1 ) {
foreach ( $terms as $candidate_term ) {
if ( $candidate_term->slug === $settings['term'] ) {
$term = $candidate_term;
break;
}
}
}
// Add hierarchical term ancestors if applicable.
$breadcrumb_items = array_merge(
$breadcrumb_items,
block_core_breadcrumbs_get_term_ancestors_items( $term->term_id, $taxonomy_name )
);
$breadcrumb_items[] = array(
'label' => $term->name,
'url' => get_term_link( $term ),
);
}
return $breadcrumb_items;
}
/**
* Registers the `core/breadcrumbs` block on the server.
*
* @since 7.0.0
*/
function register_block_core_breadcrumbs() {
register_block_type_from_metadata(
__DIR__ . '/breadcrumbs',
array(
'render_callback' => 'render_block_core_breadcrumbs',
)
);
}
add_action( 'init', 'register_block_core_breadcrumbs' );