register_meta( string $object_type, string $meta_key, array $args, string|array $deprecated = null ): bool

Description

Parameters

$object_typestring

Type of object metadata is for. Accepts 'blog', 'post', 'comment', 'term', 'user', or any other object type with an associated meta table.

$meta_keystring

Meta key to register.

$argsarray

Data used to describe the meta key when registered.

• $object_subtypestringdefault: empty

  A subtype; e.g. if the object type is "post", the post type. If left empty, the meta key will be registered on the entire object type.

• $typestring

  The type of data associated with this meta key. Valid values are 'string', 'boolean', 'integer', 'number', 'array', and 'object'.

• $labelstring

  A human-readable label of the data attached to this meta key.

• $descriptionstring

  A description of the data attached to this meta key.

• $singlebool

  Whether the meta key has one value per object, or an array of values per object.

• $defaultmixed

  The default value returned from get_metadata() if no value has been set yet. When using a non-single meta key, the default value is for the first entry. In other words, when calling get_metadata() with $single set to false, the default value given here will be wrapped in an array.

• $sanitize_callbackcallable

  A function or method to call when sanitizing $meta_key data.

• $auth_callbackcallable

  Optional. A function or method to call when performing edit_post_meta, add_post_meta, and delete_post_meta capability checks.

• $show_in_restbool|array

  Whether data associated with this meta key can be considered public and should be accessible via the REST API. A custom post type must also declare support for custom fields for registered meta to be accessible via REST. When registering complex meta values this argument may optionally be an array with 'schema' or 'prepare_callback' keys instead of a boolean.

• $revisions_enabledbool

  Whether to enable revisions support for this meta_key. Can only be used when the object type is 'post'.

$deprecatedstring|arrayoptional

Deprecated. Use $args instead.Default: null

Return

bool

True if the meta key was successfully registered in the global array, false if not. Registering a meta key with distinct sanitize and auth callbacks will fire those callbacks, but will not add to the global registry.

Hooks fired · 1

One hook fires while register_meta() runs, in this order:

1. 1
   apply_filters( register_meta_args )filterline 1485 (+50 into the body)

   Filters the registration arguments when registering meta.

Uses · 10

• apply_filters()Calls the callback functions that have been added to a filter hook.
• wp_parse_args()Merges user defined arguments into defaults array.
• _doing_it_wrong()Marks something as being incorrectly called.
• __()Retrieves the translation of $text.
• post_type_supports()Checks a post type's support for a given feature.
• is_protected_meta()Determines whether a meta key is considered protected.
• add_filter()Adds a callback function to a filter hook.
• rest_validate_value_from_schema()Validate a value based on a schema.
• is_wp_error()Checks whether the given variable is a WordPress Error.
• has_filter()Checks if any filter has been registered for a hook.

Used by · 4

• register_post_meta()Registers a meta key for posts.
• register_term_meta()Registers a meta key for terms.
• wp_create_initial_comment_meta()Register initial note status meta.
• wp_register_persisted_preferences_meta()Registers the user meta property for persisted preferences.

Source

View on Trac ↗View on GitHub ↗

1435function register_meta( $object_type, $meta_key, $args, $deprecated = null ) {1436	global $wp_meta_keys;1437 1438	if ( ! is_array( $wp_meta_keys ) ) {1439		$wp_meta_keys = array();1440	}1441 1442	$defaults = array(1443		'object_subtype'    => '',1444		'type'              => 'string',1445		'label'             => '',1446		'description'       => '',1447		'default'           => '',1448		'single'            => false,1449		'sanitize_callback' => null,1450		'auth_callback'     => null,1451		'show_in_rest'      => false,1452		'revisions_enabled' => false,1453	);1454 1455	// There used to be individual args for sanitize and auth callbacks.1456	$has_old_sanitize_cb = false;1457	$has_old_auth_cb     = false;1458 1459	if ( is_callable( $args ) ) {1460		$args = array(1461			'sanitize_callback' => $args,1462		);1463 1464		$has_old_sanitize_cb = true;1465	} else {1466		$args = (array) $args;1467	}1468 1469	if ( is_callable( $deprecated ) ) {1470		$args['auth_callback'] = $deprecated;1471		$has_old_auth_cb       = true;1472	}1473 1474	/**1475	 * Filters the registration arguments when registering meta.1476	 *1477	 * @since 4.6.01478	 *1479	 * @param array  $args        Array of meta registration arguments.1480	 * @param array  $defaults    Array of default arguments.1481	 * @param string $object_type Type of object metadata is for. Accepts 'blog', 'post', 'comment', 'term',1482	 *                            'user', or any other object type with an associated meta table.1483	 * @param string $meta_key    Meta key.1484	 */1485	$args = apply_filters( 'register_meta_args', $args, $defaults, $object_type, $meta_key );1486	unset( $defaults['default'] );1487	$args = wp_parse_args( $args, $defaults );1488 1489	// Require an item schema when registering array meta.1490	if ( false !== $args['show_in_rest'] && 'array' === $args['type'] ) {1491		if ( ! is_array( $args['show_in_rest'] ) || ! isset( $args['show_in_rest']['schema']['items'] ) ) {1492			_doing_it_wrong( __FUNCTION__, __( 'When registering an "array" meta type to show in the REST API, you must specify the schema for each array item in "show_in_rest.schema.items".' ), '5.3.0' );1493 1494			return false;1495		}1496	}1497 1498	$object_subtype = ! empty( $args['object_subtype'] ) ? $args['object_subtype'] : '';1499	if ( $args['revisions_enabled'] ) {1500		if ( 'post' !== $object_type ) {1501			_doing_it_wrong( __FUNCTION__, __( 'Meta keys cannot enable revisions support unless the object type supports revisions.' ), '6.4.0' );1502 1503			return false;1504		} elseif ( ! empty( $object_subtype ) && ! post_type_supports( $object_subtype, 'revisions' ) ) {1505			_doing_it_wrong( __FUNCTION__, __( 'Meta keys cannot enable revisions support unless the object subtype supports revisions.' ), '6.4.0' );1506 1507			return false;1508		}1509	}1510 1511	// If `auth_callback` is not provided, fall back to `is_protected_meta()`.1512	if ( empty( $args['auth_callback'] ) ) {1513		if ( is_protected_meta( $meta_key, $object_type ) ) {1514			$args['auth_callback'] = '__return_false';

History

Introduced in 3.3.0. Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 7.1.0 tag, from src/wp-includes/meta.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

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