<?php
/**
* Blocks API: WP_Block class
*
* @package WordPress
* @since 5.5.0
*/
/**
* Class representing a parsed instance of a block.
*
* @since 5.5.0
* @property array $attributes
*/
#[AllowDynamicProperties]
class WP_Block {
/**
* Original parsed array representation of block.
*
* @since 5.5.0
* @var array
*/
public $parsed_block;
/**
* Name of block.
*
* @example "core/paragraph"
*
* @since 5.5.0
* @var string|null
*/
public $name;
/**
* Block type associated with the instance.
*
* @since 5.5.0
* @var WP_Block_Type
*/
public $block_type;
/**
* Block context values.
*
* @since 5.5.0
* @var array
*/
public $context = array();
/**
* All available context of the current hierarchy.
*
* @since 5.5.0
* @var array
*/
protected $available_context = array();
/**
* Block type registry.
*
* @since 5.9.0
* @var WP_Block_Type_Registry
*/
protected $registry;
/**
* List of inner blocks (of this same class)
*
* @since 5.5.0
* @var WP_Block_List
*/
public $inner_blocks = array();
/**
* Resultant HTML from inside block comment delimiters after removing inner
* blocks.
*
* @example "...Just <!-- wp:test /--> testing..." -> "Just testing..."
*
* @since 5.5.0
* @var string
*/
public $inner_html = '';
/**
* List of string fragments and null markers where inner blocks were found
*
* @example array(
* 'inner_html' => 'BeforeInnerAfter',
* 'inner_blocks' => array( block, block ),
* 'inner_content' => array( 'Before', null, 'Inner', null, 'After' ),
* )
*
* @since 5.5.0
* @var array
*/
public $inner_content = array();
/**
* Constructor.
*
* Populates object properties from the provided block instance argument.
*
* The given array of context values will not necessarily be available on
* the instance itself, but is treated as the full set of values provided by
* the block's ancestry. This is assigned to the private `available_context`
* property. Only values which are configured to consumed by the block via
* its registered type will be assigned to the block's `context` property.
*
* @since 5.5.0
*
* @param array $block {
* An associative array of a single parsed block object. See WP_Block_Parser_Block.
*
* @type string|null $blockName Name of block.
* @type array $attrs Attributes from block comment delimiters.
* @type array $innerBlocks List of inner blocks. An array of arrays that
* have the same structure as this one.
* @type string $innerHTML HTML from inside block comment delimiters.
* @type array $innerContent List of string fragments and null markers where inner blocks were found.
* }
* @param array $available_context Optional array of ancestry context values.
* @param WP_Block_Type_Registry $registry Optional block type registry.
*/
public function __construct( $block, $available_context = array(), $registry = null ) {
$this->parsed_block = $block;
$this->name = $block['blockName'];
if ( is_null( $registry ) ) {
$registry = WP_Block_Type_Registry::get_instance();
}
$this->registry = $registry;
$this->block_type = $registry->get_registered( $this->name );
$this->available_context = $available_context;
$this->refresh_context_dependents();
}
/**
* Updates the context for the current block and its inner blocks.
*
* The method updates the context of inner blocks, if any, by passing down
* any context values the block provides (`provides_context`).
*
* If the block has inner blocks, the method recursively processes them by creating new instances of `WP_Block`
* for each inner block and updating their context based on the block's `provides_context` property.
*
* @since 6.8.0
*/
public function refresh_context_dependents() {
/*
* Merging the `$context` property here is not ideal, but for now needs to happen because of backward compatibility.
* Ideally, the `$context` property itself would not be filterable directly and only the `$available_context` would be filterable.
* However, this needs to be separately explored whether it's possible without breakage.
*/
$this->available_context = array_merge( $this->available_context, $this->context );
if ( ! empty( $this->block_type->uses_context ) ) {
foreach ( $this->block_type->uses_context as $context_name ) {
if ( array_key_exists( $context_name, $this->available_context ) ) {
$this->context[ $context_name ] = $this->available_context[ $context_name ];
}
}
}
$this->refresh_parsed_block_dependents();
}
/**
* Updates the parsed block content for the current block and its inner blocks.
*
* This method sets the `inner_html` and `inner_content` properties of the block based on the parsed
* block content provided during initialization. It ensures that the block instance reflects the
* most up-to-date content for both the inner HTML and any string fragments around inner blocks.
*
* If the block has inner blocks, this method initializes a new `WP_Block_List` for them, ensuring the
* correct content and context are updated for each nested block.
*
* @since 6.8.0
*/
public function refresh_parsed_block_dependents() {
if ( ! empty( $this->parsed_block['innerBlocks'] ) ) {
$child_context = $this->available_context;
if ( ! empty( $this->block_type->provides_context ) ) {
foreach ( $this->block_type->provides_context as $context_name => $attribute_name ) {
if ( array_key_exists( $attribute_name, $this->attributes ) ) {
$child_context[ $context_name ] = $this->attributes[ $attribute_name ];
}
}
}
$this->inner_blocks = new WP_Block_List( $this->parsed_block['innerBlocks'], $child_context, $this->registry );
}
if ( ! empty( $this->parsed_block['innerHTML'] ) ) {
$this->inner_html = $this->parsed_block['innerHTML'];
}
if ( ! empty( $this->parsed_block['innerContent'] ) ) {
$this->inner_content = $this->parsed_block['innerContent'];
}
}
/**
* Returns a value from an inaccessible property.
*
* This is used to lazily initialize the `attributes` property of a block,
* such that it is only prepared with default attributes at the time that
* the property is accessed. For all other inaccessible properties, a `null`
* value is returned.
*
* @since 5.5.0
*
* @param string $name Property name.
* @return array|null Prepared attributes, or null.
*/
public function __get( $name ) {
if ( 'attributes' === $name ) {
$this->attributes = $this->parsed_block['attrs'] ??
array();
if ( ! is_null( $this->block_type ) ) {
$this->attributes = $this->block_type->prepare_attributes_for_render( $this->attributes );
}
return $this->attributes;
}
return null;
}
/**
* Processes the block bindings and updates the block attributes with the values from the sources.
*
* A block might contain bindings in its attributes. Bindings are mappings
* between an attribute of the block and a source. A "source" is a function
* registered with `register_block_bindings_source()` that defines how to
* retrieve a value from outside the block, e.g. from post meta.
*
* This function will process those bindings and update the block's attributes
* with the values coming from the bindings.
*
* ### Example
*
* The "bindings" property for an Image block might look like this:
*
* ```json
* {
* "metadata": {
* "bindings": {
* "title": {
* "source": "core/post-meta",
* "args": { "key": "text_custom_field" }
* },
* "url": {
* "source": "core/post-meta",
* "args": { "key": "url_custom_field" }
* }
* }
* }
* }
* ```
*
* The above example will replace the `title` and `url` attributes of the Image
* block with the values of the `text_custom_field` and `url_custom_field` post meta.
*
* @since 6.5.0
* @since 6.6.0 Handle the `__default` attribute for pattern overrides.
* @since 6.7.0 Return any updated bindings metadata in the computed attributes.
*
* @return array The computed block attributes for the provided block bindings.
*/
private function process_block_bindings() {
$block_type = $this->name;
$parsed_block = $this->parsed_block;
$computed_attributes = array();
$supported_block_attributes = get_block_bindings_supported_attributes( $block_type );
// If the block doesn't have the bindings property, isn't one of the supported
// block types, or the bindings property is not an array, return the block content.
if (
empty( $supported_block_attributes ) ||
empty( $parsed_block['attrs']['metadata']['bindings'] ) ||
! is_array( $parsed_block['attrs']['metadata']['bindings'] )
) {
return $computed_attributes;
}
$bindings = $parsed_block['attrs']['metadata']['bindings'];
/*
* If the default binding is set for pattern overrides, replace it
* with a pattern override binding for all supported attributes.
*/
if (
isset( $bindings['__default']['source'] ) &&
'core/pattern-overrides' === $bindings['__default']['source']
) {
$updated_bindings = array();
/*
* Build a binding array of all supported attributes.
* Note that this also omits the `__default` attribute from the
* resulting array.
*/
foreach ( $supported_block_attributes as $attribute_name ) {
// Retain any non-pattern override bindings that might be present.
$updated_bindings[ $attribute_name ] = $bindings[ $attribute_name ] ?? array( 'source' => 'core/pattern-overrides' );
}
$bindings = $updated_bindings;
/*
* Update the bindings metadata of the computed attributes.
* This ensures the block receives the expanded __default binding metadata when it renders.
*/
$computed_attributes['metadata'] = array_merge(
$parsed_block['attrs']['metadata'],
array( 'bindings' => $bindings )
);
}
foreach ( $bindings as $attribute_name => $block_binding ) {
// If the attribute is not in the supported list, process next attribute.
if ( ! in_array( $attribute_name, $supported_block_attributes, true ) ) {
continue;
}
// If no source is provided, or that source is not registered, process next attribute.
if ( ! isset( $block_binding['source'] ) || ! is_string( $block_binding['source'] ) ) {
continue;
}
$block_binding_source = get_block_bindings_source( $block_binding['source'] );
if ( null === $block_binding_source ) {
continue;
}
// Adds the necessary context defined by the source.
if ( ! empty( $block_binding_source->uses_context ) ) {
foreach ( $block_binding_source->uses_context as $context_name ) {
if ( array_key_exists( $context_name, $this->available_context ) ) {
$this->context[ $context_name ] = $this->available_context[ $context_name ];
}
}
}
$source_args = ! empty( $block_binding['args'] ) && is_array( $block_binding['args'] ) ? $block_binding['args'] : array();
$source_value = $block_binding_source->get_value( $source_args, $this, $attribute_name );
// If the value is not null, process the HTML based on the block and the attribute.
if ( ! is_null( $source_value ) ) {
$computed_attributes[ $attribute_name ] = $source_value;
}
}
return $computed_attributes;
}
/**
* Depending on the block attribute name, replace its value in the HTML based on the value provided.
*
* @since 6.5.0
* @since 7.1.0 Added the optional `$inner_block_offsets` parameter.
*
* @param string $block_content Block content.
* @param string $attribute_name The attribute name to replace.
* @param mixed $source_value The value used to replace in the HTML.
* @param int[] $inner_block_offsets Optional. Byte offsets where each inner block's
* rendered output begins. Default empty array.
* @return string The modified block content.
*/
private function replace_html( string $block_content, string $attribute_name, $source_value, array $inner_block_offsets = array() ) {
$block_type = $this->block_type;
if ( ! isset( $block_type->attributes[ $attribute_name ]['source'] ) ) {
return $block_content;
}
// Depending on the attribute source, the processing will be different.
switch ( $block_type->attributes[ $attribute_name ]['source'] ) {
case 'html':
case 'rich-text':
$block_reader = self::get_block_bindings_processor( $block_content );
// TODO: Support for CSS selectors whenever they are ready in the HTML API.
// In the meantime, support comma-separated selectors by exploding them into an array.
$selectors = explode( ',', $block_type->attributes[ $attribute_name ]['selector'] );
// Add a bookmark to the first tag to be able to iterate over the selectors.
$block_reader->next_tag();
$block_reader->set_bookmark( 'iterate-selectors' );
foreach ( $selectors as $selector ) {
// If the parent tag, or any of its children, matches the selector, replace the HTML.
if ( strcasecmp( $block_reader->get_tag(), $selector ) === 0 || $block_reader->next_tag(
array(
'tag_name' => $selector,
)
) ) {
/*
* TODO: Use `WP_HTML_Processor::set_inner_html()` once it's available.
* Any replacement must preserve already-rendered inner block
* markup verbatim (it may come from dynamic blocks), so it
* cannot re-serialize the element's contents. Until an API with
* that guarantee exists, the replacement is spliced by byte
* offset, leaving inner block output untouched.
*/
$block_reader->release_bookmark( 'iterate-selectors' );
$block_reader->replace_rich_text( wp_kses_post( $source_value ), $inner_block_offsets );
return $block_reader->get_updated_html();
} else {
$block_reader->seek( 'iterate-selectors' );
}
}
$block_reader->release_bookmark( 'iterate-selectors' );
return $block_content;
case 'attribute':
$amended_content = new WP_HTML_Tag_Processor( $block_content );
if ( ! $amended_content->next_tag(
array(
// TODO: build the query from CSS selector.
'tag_name' => $block_type->attributes[ $attribute_name ]['selector'],
)
) ) {
return $block_content;
}
$amended_content->set_attribute( $block_type->attributes[ $attribute_name ]['attribute'], $source_value );
return $amended_content->get_updated_html();
default:
return $block_content;
}
}
private static function get_block_bindings_processor( string $block_content ) {
$internal_processor_class = new class('', WP_HTML_Processor::CONSTRUCTOR_UNLOCK_CODE) extends WP_HTML_Processor {
/**
* Replace the rich text content between a tag opener and matching closer.
*
* When stopped on a tag opener, replace the content enclosed by it and its
* matching closer with the provided rich text.
*
* If byte offsets of inner blocks' rendered output are provided, the
* replacement stops at the first inner block found inside the element,
* preserving any markup produced by nested inner blocks (e.g. a List
* block nested inside a List Item).
*
* @param string $rich_text The rich text to replace the original content with.
* @param int[] $inner_block_offsets Optional. Byte offsets in the source HTML where
* inner blocks' rendered output begins. Default empty array.
* @return bool True on success.
*/
public function replace_rich_text( $rich_text, $inner_block_offsets = array() ) {
if ( $this->is_tag_closer() || ! $this->expects_closer() ) {
return false;
}
$depth = $this->get_current_depth();
$tag_name = $this->get_tag();
$this->set_bookmark( '_wp_block_bindings' );
// The bookmark names are prefixed with `_` so the key below has an extra `_`.
$tag_opener = $this->bookmarks['__wp_block_bindings'];
$start = $tag_opener->start + $tag_opener->length;
// Find matching tag closer.
while ( $this->next_token() && $this->get_current_depth() >= $depth ) {
}
if ( ! $this->is_tag_closer() || $tag_name !== $this->get_tag() ) {
return false;
}
$this->set_bookmark( '_wp_block_bindings' );
$tag_closer = $this->bookmarks['__wp_block_bindings'];
$end = $tag_closer->start;
/*
* Stop at the first inner block that renders inside this element so
* its markup is preserved. The block's own rich text always precedes
* its inner blocks, so replacing up to the first inner block offset
* replaces only that rich text. Offsets are recorded during render in
* the same byte coordinates as this fragment, and are in ascending
* order, so the first match is the earliest inner block.
*
* The lower bound is inclusive of `$start`: when an inner block
* begins immediately, with no leading rich text, the (empty) rich
* text is still replaced instead of the inner block markup.
*/
foreach ( $inner_block_offsets as $inner_block_offset ) {
if ( $inner_block_offset >= $start && $inner_block_offset < $end ) {
$end = $inner_block_offset;
break;
}
}
$this->lexical_updates[] = new WP_HTML_Text_Replacement(
$start,
$end - $start,
$rich_text
);
return true;
}
};
return $internal_processor_class::create_fragment( $block_content );
}
/**
* Generates the render output for the block.
*
* @since 5.5.0
* @since 6.5.0 Added block bindings processing.
* @since 7.1.0 Preserve inner blocks when binding a rich text attribute.
*
* @global WP_Post $post Global post object.
*
* @param array $options {
* Optional options object.
*
* @type bool $dynamic Defaults to 'true'. Optionally set to false to avoid using the block's render_callback.
* }
* @return string Rendered block output.
*/
public function render( $options = array() ) {
global $post;
$before_wp_enqueue_scripts_count = did_action( 'wp_enqueue_scripts' );
// Capture the current assets queues.
$before_styles_queue = wp_styles()->queue;
$before_scripts_queue = wp_scripts()->queue;
$before_script_modules_queue = wp_script_modules()->get_queue();
/*
* There can be only one root interactive block at a time because the rendered HTML of that block contains
* the rendered HTML of all its inner blocks, including any interactive block.
*/
static $root_interactive_block = null;
/**
* Filters whether Interactivity API should process directives.
*
* @since 6.6.0
*
* @param bool $enabled Whether the directives processing is enabled.
*/
$interactivity_process_directives_enabled = apply_filters( 'interactivity_process_directives', true );
if (
$interactivity_process_directives_enabled && null === $root_interactive_block && (
( isset( $this->block_type->supports['interactivity'] ) && true === $this->block_type->supports['interactivity'] ) ||
! empty( $this->block_type->supports['interactivity']['interactive'] )
)
) {
$root_interactive_block = $this;
}
$options = wp_parse_args(
$options,
array(
'dynamic' => true,
)
);
// Process the block bindings and get attributes updated with the values from the sources.
$computed_attributes = $this->process_block_bindings();
if ( ! empty( $computed_attributes ) ) {
// Merge the computed attributes with the original attributes.
$this->attributes = array_merge( $this->attributes, $computed_attributes );
}
$is_dynamic = $options['dynamic'] && $this->name && null !== $this->block_type && $this->block_type->is_dynamic();
$block_content = '';
/*
* Byte offsets in $block_content where each inner block's rendered output
* begins. Block bindings rich-text replacement uses these to stop at the
* first inner block inside a selector, so it replaces only the block's own
* rich text and never the markup produced by nested inner blocks.
*
* They are only collected when the block has bound attributes to resolve;
* otherwise they are never read, so recording them would add work to every
* block render for no benefit.
*/
$inner_block_offsets = array();
$collect_offsets = ! empty( $computed_attributes );
if ( ! $options['dynamic'] || empty( $this->block_type->skip_inner_blocks ) ) {
$index = 0;
foreach ( $this->inner_content as $chunk ) {
if ( is_string( $chunk ) ) {
$block_content .= $chunk;
} else {
if ( $collect_offsets ) {
$inner_block_offsets[] = strlen( $block_content );
}
$inner_block = $this->inner_blocks[ $index ];
$parent_block = $this;
/** This filter is documented in wp-includes/blocks.php */
$pre_render = apply_filters( 'pre_render_block', null, $inner_block->parsed_block, $parent_block );
if ( ! is_null( $pre_render ) ) {
$block_content .= $pre_render;
} else {
$source_block = $inner_block->parsed_block;
$inner_block_context = $inner_block->context;
/** This filter is documented in wp-includes/blocks.php */
$inner_block->parsed_block = apply_filters( 'render_block_data', $inner_block->parsed_block, $source_block, $parent_block );
/** This filter is documented in wp-includes/blocks.php */
$inner_block->context = apply_filters( 'render_block_context', $inner_block->context, $inner_block->parsed_block, $parent_block );
/*
* The `refresh_context_dependents()` method already calls `refresh_parsed_block_dependents()`.
* Therefore the second condition is irrelevant if the first one is satisfied.
*/
if ( $inner_block->context !== $inner_block_context ) {
$inner_block->refresh_context_dependents();
} elseif ( $inner_block->parsed_block !== $source_block ) {
$inner_block->refresh_parsed_block_dependents();
}
$block_content .= $inner_block->render();
}
++$index;
}
}
}
if ( ! empty( $computed_attributes ) && ! empty( $block_content ) ) {
foreach ( $computed_attributes as $attribute_name => $source_value ) {
$updated_block_content = $this->replace_html( $block_content, $attribute_name, $source_value, $inner_block_offsets );
/*
* The offsets describe $block_content as it was assembled. A
* replacement that modifies the markup shifts byte positions, so
* once the content changes the remaining attributes fall back to
* offset-free replacement rather than clamp at a stale position.
* Attributes that leave the markup untouched keep the offsets
* valid: the computed `metadata` attribute produced by a pattern
* overrides `__default` binding has no HTML source, so it must
* not invalidate the offsets for the rich text that follows it.
*/
if ( $updated_block_content !== $block_content ) {
$inner_block_offsets = array();
}
$block_content = $updated_block_content;
}
}
if ( $is_dynamic ) {
$global_post = $post;
$parent = WP_Block_Supports::$block_to_render;
WP_Block_Supports::$block_to_render = $this->parsed_block;
$block_content = (string) call_user_func( $this->block_type->render_callback, $this->attributes, $block_content, $this );
WP_Block_Supports::$block_to_render = $parent;
$post = $global_post;
}
if ( ( ! empty( $this->block_type->script_handles ) ) ) {
foreach ( $this->block_type->script_handles as $script_handle ) {
wp_enqueue_script( $script_handle );
}
}
if ( ! empty( $this->block_type->view_script_handles ) ) {
foreach ( $this->block_type->view_script_handles as $view_script_handle ) {
wp_enqueue_script( $view_script_handle );
}
}
if ( ! empty( $this->block_type->view_script_module_ids ) ) {
foreach ( $this->block_type->view_script_module_ids as $view_script_module_id ) {
wp_enqueue_script_module( $view_script_module_id );
}
}
/*
* For Core blocks, these styles are only enqueued if `wp_should_load_separate_core_block_assets()` returns
* true. Otherwise these `wp_enqueue_style()` calls will not have any effect, as the Core blocks are relying on
* the combined 'wp-block-library' stylesheet instead, which is unconditionally enqueued.
*/
if ( ( ! empty( $this->block_type->style_handles ) ) ) {
foreach ( $this->block_type->style_handles as $style_handle ) {
wp_enqueue_style( $style_handle );
}
}
if ( ( ! empty( $this->block_type->view_style_handles ) ) ) {
foreach ( $this->block_type->view_style_handles as $view_style_handle ) {
wp_enqueue_style( $view_style_handle );
}
}
/**
* Filters the content of a single block.
*
* @since 5.0.0
* @since 5.9.0 The `$instance` parameter was added.
*
* @param string $block_content The block content.
* @param array $block The full block, including name and attributes.
* @param WP_Block $instance The block instance.
*/
$block_content = apply_filters( 'render_block', $block_content, $this->parsed_block, $this );
/**
* Filters the content of a single block.
*
* The dynamic portion of the hook name, `$name`, refers to
* the block name, e.g. "core/paragraph".
*
* @since 5.7.0
* @since 5.9.0 The `$instance` parameter was added.
*
* @param string $block_content The block content.
* @param array $block The full block, including name and attributes.
* @param WP_Block $instance The block instance.
*/
$block_content = apply_filters( "render_block_{$this->name}", $block_content, $this->parsed_block, $this );
if ( $root_interactive_block === $this ) {
// The root interactive block has finished rendering. Time to process directives.
$block_content = wp_interactivity_process_directives( $block_content );
$root_interactive_block = null;
}
// Capture the new assets enqueued during rendering, and restore the queues the state prior to rendering.
$after_styles_queue = wp_styles()->queue;
$after_scripts_queue = wp_scripts()->queue;
$after_script_modules_queue = wp_script_modules()->get_queue();
/*
* As a very special case, a dynamic block may in fact include a call to wp_head() (and thus wp_enqueue_scripts()),
* in which all of its enqueued assets are targeting wp_footer. In this case, nothing would be printed, but this
* shouldn't indicate that the just-enqueued assets should be dequeued due to it being an empty block.
*/
$just_did_wp_enqueue_scripts = ( did_action( 'wp_enqueue_scripts' ) !== $before_wp_enqueue_scripts_count );
$has_new_styles = ( $before_styles_queue !== $after_styles_queue );
$has_new_scripts = ( $before_scripts_queue !== $after_scripts_queue );
$has_new_script_modules = ( $before_script_modules_queue !== $after_script_modules_queue );
// Dequeue the newly enqueued assets with the existing assets if the rendered block was empty & wp_enqueue_scripts did not fire.
if (
! $just_did_wp_enqueue_scripts &&
( $has_new_styles || $has_new_scripts || $has_new_script_modules ) &&
(
trim( $block_content ) === '' &&
/**
* Filters whether to enqueue assets for a block which has no rendered content.
*
* @since 6.9.0
*
* @param bool $enqueue Whether to enqueue assets.
* @param string $block_name Block name.
*/
! (bool) apply_filters( 'enqueue_empty_block_content_assets', false, $this->name )
)
) {
foreach ( array_diff( $after_styles_queue, $before_styles_queue ) as $handle ) {
wp_dequeue_style( $handle );
}
foreach ( array_diff( $after_scripts_queue, $before_scripts_queue ) as $handle ) {
wp_dequeue_script( $handle );
}
foreach ( array_diff( $after_script_modules_queue, $before_script_modules_queue ) as $handle ) {
wp_dequeue_script_module( $handle );
}
}
return $block_content;
}
}