Persistence query for LevelDB

Akka persistence query provides the functionality to read the journal and also receive live events that are getting persisted thanks to an Akka Stream. Implementations of Akka persistence query differ depending on which underlying technology we select. In this recipe, we will be using the LevelDB plugin to query all current events in a journal, and we will also create a stream to subscribe to real-time events. To learn more about Akka Streams, refer to Chapter 8, Akka Streams.

Getting ready

To step through this recipe, we need to import the hell0-Akka project in the IDE; other prerequisites are the same as earlier as we have downloaded the akka-persistence dependency. We will also need the persistence query dependency. We will also make use of the classes created in the Recovering state of the actor recipe for this recipe.

How to do it…

For this recipe, we need to perform the following steps:

1. First, we need to get the required dependencies. Open build.sbt and make...