Octoconf

What is it?

This repo is just a example of my talk at the ElixirConf EU 2018. Here you find a fairly simple approach of how to use GenStage e GenServer to apply back-pressure when consuming differents queues.

Why this approach?

The main reason is due to third party constraints. When you are dealing the applications that are not in your domain, specially with request limits and unexpected unaviability, we need to make sure our process keep going without overloading the nodes.

After Everything is in Place

After all the abstractions are implemented, you just need to declare the name of the queue, which module is going to handle the messages and how many messages should be processed concurrently. Here is a config example:

config :octoconf,
  queues: [
    %{
      name: "stock",
      handler: Octoconf.Handlers.Product,
      concurrency: 10
    },
    %{
      name: "invoice",
      handler: Octoconf.Handlers.Order,
      concurrency: 20
    }
  ]