title: RabbitMQ message processing by specific order
body: <p>i would like to know  what is the best practice for processing messages from the queue if i need to make sure that another message (has same product Id) at the same time is not being processed by another consumer.
  my problem is that if someone places and order with product ids and another message comes with same products i want to process them one by one, but not in parallel. 
  i am thinking of using redis where i would save the ids that are being processed and clear them after the processing is over. But maybe there are some better solutions for this kind of situation.</p>