Using Cassandra for our persistent store

In Chapter 1, Building a Better Reactive App, in the section titled Cassandra to the rescue, I talked about why Cassandra will be a good fit for our bookstore application. It's distributed and highly available with great performance on the write side. It seems really tailor-made to fit what an event sourced application needs to do. In this section, we will get it installed and then go over the Akka config, which you will need to use it for both the AsyncWriteJournal and the SnapshotStore.

Installing Cassandra

Thanks to our decision to use Docker, there is no real install that we need to do to get Cassandra set up on our local systems. In this chapter, in the Docker Compose configuration (contained in the docker-compose.yml file found at the root of the bookstore app directory structure) we have replaced Postgres with Cassandra. All we need to do is launch the bookstore app as we have done previously (via docket-build.sh and then launch.sh) and we will...