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function is not described

WP_REST_Meta_Fields::update_meta_value() protected WP 4.7.0

Updates a meta value for an object.

{} It's a method of the class: WP_REST_Meta_Fields{}

No Hooks.

Return

true/false/WP_Error. True if the meta field was updated, WP_Error otherwise.

Usage

// protected - for code of main (parent) or child class
$result = $this->update_meta_value( $object_id, $meta_key, $name, $value );
$object_id(int) (required)
Object ID to update.
$meta_key(string) (required)
Key for the custom field.
$name(string) (required)
Name for the field that is exposed in the REST API.
$value(mixed) (required)
Updated value.

Changelog

Since 4.7.0 Introduced.

Code of WP_REST_Meta_Fields::update_meta_value() WP 5.5.1

<?php
protected function update_meta_value( $object_id, $meta_key, $name, $value ) {
	$meta_type = $this->get_meta_type();

	if ( ! current_user_can( "edit_{$meta_type}_meta", $object_id, $meta_key ) ) {
		return new WP_Error(
			'rest_cannot_update',
			/* translators: %s: Custom field key. */
			sprintf( __( 'Sorry, you are not allowed to edit the %s custom field.' ), $name ),
			array(
				'key'    => $name,
				'status' => rest_authorization_required_code(),
			)
		);
	}

	// Do the exact same check for a duplicate value as in update_metadata() to avoid update_metadata() returning false.
	$old_value = get_metadata( $meta_type, $object_id, $meta_key );
	$subtype   = get_object_subtype( $meta_type, $object_id );

	if ( 1 === count( $old_value ) && $this->is_meta_value_same_as_stored_value( $meta_key, $subtype, $old_value[0], $value ) ) {
		return true;
	}

	if ( ! update_metadata( $meta_type, $object_id, wp_slash( $meta_key ), wp_slash_strings_only( $value ) ) ) {
		return new WP_Error(
			'rest_meta_database_error',
			/* translators: %s: Custom field key. */
			sprintf( __( 'Could not update the meta value of %s in database.' ), $meta_key ),
			array(
				'key'    => $name,
				'status' => WP_Http::INTERNAL_SERVER_ERROR,
			)
		);
	}

	return true;
}