title: In Kubernetes, how do I autoscale based on the size of a queue?
body: <p>Suppose I have a RabbitMQ instance and a set of pods that pick messages from RabbitMQ and process them. How do I make Kubernetes increase the number of pods as the queue size increases?</p>
  
  <p>(I'm mentioning RabbitMQ, but that's just an example. Pick your favorite message queue software or load balancer if you wish.)</p>