As the sun rises and the forest mist clears, and the clouds return and the caves darken, these changes of light and shadow are the morning and evening in the mountains. Wildflowers bloom with their subtle fragrance, fine trees flourish with their dense shade, the wind and frost are pure and clean, and the water recedes to reveal the rocks—these are the four seasons in the mountains. Going out in the morning and returning in the evening, the scenery of the four seasons is different, and the joy is endless.至于负者歌于途,行者休于树,前者呼,后者应,伛偻提携,往来而不绝者,滁人游也。临溪而渔,溪深而鱼肥,酿泉为酒,泉香而酒洌,山肴野蔌,杂然而前陈者,太守宴也。宴酣之乐,非丝非竹,射者中,弈者胜,觥筹交错,起坐而喧哗者,众宾欢也。苍颜白发,颓然乎其间者,太守醉也。
<?php
/**
* Block Bindings API: WP_Block_Bindings_Registry class.
*
* Supports overriding content in blocks by connecting them to different sources.
*
* @package WordPress
* @subpackage Block Bindings
* @since 6.5.0
*/
/**
* Core class used for interacting with block bindings sources.
*
* @since 6.5.0
*/
final class WP_Block_Bindings_Registry {
/**
* Holds the registered block bindings sources, keyed by source identifier.
*
* @since 6.5.0
* @var WP_Block_Bindings_Source[]
*/
private $sources = array();
/**
* Container for the main instance of the class.
*
* @since 6.5.0
* @var WP_Block_Bindings_Registry|null
*/
private static $instance = null;
/**
* Supported source properties that can be passed to the registered source.
*
* @since 6.5.0
* @var string[]
*/
private $allowed_source_properties = array(
'label',
'get_value_callback',
'uses_context',
);
/**
* Registers a new block bindings source.
*
* This is a low-level method. For most use cases, it is recommended to use
* the `register_block_bindings_source()` function instead.
*
* @see register_block_bindings_source()
*
* Sources are used to override block's original attributes with a value
* coming from the source. Once a source is registered, it can be used by a
* block by setting its `metadata.bindings` attribute to a value that refers
* to the source.
*
* @since 6.5.0
*
* @param string $source_name The name of the source. It must be a string containing a namespace prefix, i.e.
* `my-plugin/my-custom-source`. It must only contain lowercase alphanumeric
* characters, the forward slash `/` and dashes.
* @param array $source_properties {
* The array of arguments that are used to register a source.
*
* @type string $label The label of the source.
* @type callable $get_value_callback A callback executed when the source is processed during block rendering.
* The callback should have the following signature:
*
* `function( $source_args, $block_instance, $attribute_name ): mixed`
* - @param array $source_args Array containing source arguments
* used to look up the override value,
* i.e. {"key": "foo"}.
* - @param WP_Block $block_instance The block instance.
* - @param string $attribute_name The name of the target attribute.
* The callback has a mixed return type; it may return a string to override
* the block's original value, null, false to remove an attribute, etc.
* @type string[] $uses_context Optional. Array of values to add to block `uses_context` needed by the source.
* }
* @return WP_Block_Bindings_Source|false Source when the registration was successful, or `false` on failure.
*/
public function register( string $source_name, array $source_properties ) {
if ( ! is_string( $source_name ) ) {
_doing_it_wrong(
__METHOD__,
__( 'Block bindings source name must be a string.' ),
'6.5.0'
);
return false;
}
if ( preg_match( '/[A-Z]+/', $source_name ) ) {
_doing_it_wrong(
__METHOD__,
__( 'Block bindings source names must not contain uppercase characters.' ),
'6.5.0'
);
return false;
}
$name_matcher = '/^[a-z0-9-]+\/[a-z0-9-]+$/';
if ( ! preg_match( $name_matcher, $source_name ) ) {
_doing_it_wrong(
__METHOD__,
__( 'Block bindings source names must contain a namespace prefix. Example: my-plugin/my-custom-source' ),
'6.5.0'
);
return false;
}
if ( $this->is_registered( $source_name ) ) {
_doing_it_wrong(
__METHOD__,
/* translators: %s: Block bindings source name. */
sprintf( __( 'Block bindings source "%s" already registered.' ), $source_name ),
'6.5.0'
);
return false;
}
// Validates that the source properties contain the label.
if ( ! isset( $source_properties['label'] ) ) {
_doing_it_wrong(
__METHOD__,
__( 'The $source_properties must contain a "label".' ),
'6.5.0'
);
return false;
}
// Validates that the source properties contain the get_value_callback.
if ( ! isset( $source_properties['get_value_callback'] ) ) {
_doing_it_wrong(
__METHOD__,
__( 'The $source_properties must contain a "get_value_callback".' ),
'6.5.0'
);
return false;
}
// Validates that the get_value_callback is a valid callback.
if ( ! is_callable( $source_properties['get_value_callback'] ) ) {
_doing_it_wrong(
__METHOD__,
__( 'The "get_value_callback" parameter must be a valid callback.' ),
'6.5.0'
);
return false;
}
// Validates that the uses_context parameter is an array.
if ( isset( $source_properties['uses_context'] ) && ! is_array( $source_properties['uses_context'] ) ) {
_doing_it_wrong(
__METHOD__,
__( 'The "uses_context" parameter must be an array.' ),
'6.5.0'
);
return false;
}
if ( ! empty( array_diff( array_keys( $source_properties ), $this->allowed_source_properties ) ) ) {
_doing_it_wrong(
__METHOD__,
__( 'The $source_properties array contains invalid properties.' ),
'6.5.0'
);
return false;
}
$source = new WP_Block_Bindings_Source(
$source_name,
$source_properties
);
$this->sources[ $source_name ] = $source;
return $source;
}
/**
* Unregisters a block bindings source.
*
* @since 6.5.0
*
* @param string $source_name Block bindings source name including namespace.
* @return WP_Block_Bindings_Source|false The unregistered block bindings source on success and `false` otherwise.
*/
public function unregister( string $source_name ) {
if ( ! $this->is_registered( $source_name ) ) {
_doing_it_wrong(
__METHOD__,
/* translators: %s: Block bindings source name. */
sprintf( __( 'Block binding "%s" not found.' ), $source_name ),
'6.5.0'
);
return false;
}
$unregistered_source = $this->sources[ $source_name ];
unset( $this->sources[ $source_name ] );
return $unregistered_source;
}
/**
* Retrieves the list of all registered block bindings sources.
*
* @since 6.5.0
*
* @return WP_Block_Bindings_Source[] The array of registered sources.
*/
public function get_all_registered() {
return $this->sources;
}
/**
* Retrieves a registered block bindings source.
*
* @since 6.5.0
*
* @param string $source_name The name of the source.
* @return WP_Block_Bindings_Source|null The registered block bindings source, or `null` if it is not registered.
*/
public function get_registered( string $source_name ) {
if ( ! $this->is_registered( $source_name ) ) {
return null;
}
return $this->sources[ $source_name ];
}
/**
* Checks if a block bindings source is registered.
*
* @since 6.5.0
*
* @param string|null $source_name The name of the source.
* @return bool `true` if the block bindings source is registered, `false` otherwise.
*/
public function is_registered( $source_name ) {
return isset( $source_name, $this->sources[ $source_name ] );
}
/**
* Wakeup magic method.
*
* @since 6.5.0
*/
public function __wakeup() {
if ( ! $this->sources ) {
return;
}
if ( ! is_array( $this->sources ) ) {
throw new UnexpectedValueException();
}
foreach ( $this->sources as $value ) {
if ( ! $value instanceof WP_Block_Bindings_Source ) {
throw new UnexpectedValueException();
}
}
}
/**
* Utility method to retrieve the main instance of the class.
*
* The instance will be created if it does not exist yet.
*
* @since 6.5.0
*
* @return WP_Block_Bindings_Registry The main instance.
*/
public static function get_instance() {
if ( null === self::$instance ) {
self::$instance = new self();
}
return self::$instance;
}
}