export interface QueueInterface { /**
     * The Queue driver.
     */ driver ? : QueueInterface ; /**
     * Add a new event with data to queue.
     */ addToQueue ( queueName , data ? ) : Promise < void > ; /**
     * Register the code to run when handing the queue.
     */ processQueue ( queueName , callback ) : Promise < void > ; /**
     * Clear the queues for a graceful shutdown.
     */ clear ( ) : Promise < void > ; }