Sets a transient for elements in a WP REST API call

wp-rest-transient-example.php

<?php

function yournamespace_rest_transient_example() {

	//check for transient first
	$data = get_transient( 'yournamespace_data_example' );

	if ( !empty( $data ) ) {

		$data = $terms_transient;
	
	//generate output and then save to transient
	} else {

		//do some stuff here and set result to $data
		
		$data = custom_remote_post_call();

		//cache for 2 days
		set_transient( 'yournamespace_data_example', $data, DAY_IN_SECONDS * 2 );
	
	}
	
	$result = new WP_REST_Response( $data, 200 );

	return $result;

}