register_rest_field( string|array $object_type, string $attribute, array $args = array() )

Registers a new field on an existing ClassicPress object type.

Parameters

$object_type

(Required) Object(s) the field is being registered to, "post"|"term"|"comment" etc.

$attribute

(Required) The attribute name.

$args

(Optional) An array of arguments used to handle the registered field.

'get_callback'
(string|array|null) Optional. The callback function used to retrieve the field value. Default is 'null', the field will not be returned in the response.
'update_callback'
(string|array|null) Optional. The callback function used to set and update the field value. Default is 'null', the value cannot be set or updated.
'schema'
(string|array|null) Optional. The callback function used to create the schema for this field. Default is 'null', no schema entry will be returned.

Default value: array()

Source

File: wp-includes/rest-api.php

function register_rest_field( $object_type, $attribute, $args = array() ) {
	$defaults = array(
		'get_callback'    => null,
		'update_callback' => null,
		'schema'          => null,
	);

	$args = wp_parse_args( $args, $defaults );

	global $wp_rest_additional_fields;

	$object_types = (array) $object_type;

	foreach ( $object_types as $object_type ) {
		$wp_rest_additional_fields[ $object_type ][ $attribute ] = $args;
	}
}

Expand Source Code View on GitHub

Uses

Uses
Uses	Description
wp-includes/functions.php: wp_parse_args()	Merge user defined arguments into defaults array.

Used By

Used By
Used By	Description
wp-includes/rest-api/fields/class-wp-rest-meta-fields.php: WP_REST_Meta_Fields::register_field()	Registers the meta field.

Changelog

Changelog
Version	Description
WP-4.7.0	Introduced.