wp-includes/rest-api/fields/class-wp-rest-meta-fields.php:279Updates multiple meta values for an object.
$object_idint$meta_keystring$namestring$valuesarraytrue|WP_Error protected function update_multi_meta_value( $object_id, $meta_key, $name, $values ) { $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(), ) ); } $current_values = get_metadata_raw( $meta_type, $object_id, $meta_key, false ); $subtype = get_object_subtype( $meta_type, $object_id ); if ( ! is_array( $current_values ) ) { $current_values = array(); } $to_remove = $current_values; $to_add = $values; foreach ( $to_add as $add_key => $value ) { $remove_keys = array_keys( array_filter( $current_values, function ( $stored_value ) use ( $meta_key, $subtype, $value ) { return $this->is_meta_value_same_as_stored_value( $meta_key, $subtype, $stored_value, $value ); } ) ); if ( empty( $remove_keys ) ) { continue; } if ( count( $remove_keys ) > 1 ) { // To remove, we need to remove first, then add, so don't touch. continue; } $remove_key = $remove_keys[0]; unset( $to_remove[ $remove_key ] ); unset( $to_add[ $add_key ] ); } /* * `delete_metadata` removes _all_ instances of the value, so only call once. Otherwise, * `delete_metadata` will return false for subsequent calls of the same value. * Use serialization to produce a predictable string that can be used by array_unique. */ $to_remove = array_map( 'maybe_unserialize', array_unique( array_map( 'maybe_serialize', $to_remove ) ) ); foreach ( $to_remove as $value ) { if ( ! delete_metadata( $meta_type, $object_id, wp_slash( $meta_key ), wp_slash( $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, ) ); } } foreach ( $to_add as $value ) { if ( ! add_metadata( $meta_type, $object_id, wp_slash( $meta_key ), wp_slash( $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,Introduced in 4.7.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/rest-api/fields/class-wp-rest-meta-fields.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.