AsadaGuitar / akka-cqrs-counter

Counter application built on CQRS using akka and http4s.

akka-cqrs-counter

Akka Projection Version 1.2.5 sample project.
The system configuration assumes CQRS, EventSourcing.
This project is not intended for a production environment. Please use this information to get an overall picture.

Features

• Scala version 2.13.8
• Akka
• http4s
• Slick3
• Event Sourcing
• CQRS

System Architecture

Diagrams

Description & Dependency Libraries

• Write API
  • This project builds ClusterSharding and provides event writing.
  • The project is structured around Akka.
  • Dependency Libraries
    • "com.typesafe.akka" %% "akka-actor-typed" % akkaVersion
    • "com.typesafe.akka" %% "akka-persistence-typed" % akkaVersion
    • "com.typesafe.akka" %% "akka-persistence-cassandra" % cassandraPersistenceVersion
    • "com.typesafe.akka" %% "akka-cluster-sharding-typed" % akkaVersion
    • "com.typesafe.akka" %% "akka-http" % akkaHttpVersion
• Read API
  • read-api provides an Api to get a simple Counter. Also, due to Akka license changes, this project uses http4s.
  • Dependency Libraries
    • "org.http4s" %% "http4s-server" % http4sVersion
    • "org.http4s" %% "http4s-blaze-server" % http4sVersion
    • "org.http4s" %% "http4s-dsl" % http4sVersion
    • "com.typesafe.slick" %% "slick" % slickVersion
    • "org.postgresql" % "postgresql" % postgresVersion
• Projection
  • It retrieves events written by write-api and builds a set of relational data in RDMS used by read-api.
  • Dependency Libraries
    • "com.typesafe.akka" %% "akka-persistence-typed" % akkaVersion
    • "com.typesafe.akka" %% "akka-persistence-cassandra" % cassandraPersistenceVersion
    • "com.typesafe.akka" %% "akka-cluster-sharding-typed" % akkaVersion
    • "com.lightbend.akka" %% "akka-projection-eventsourced" % akkaProjectionVersion
    • "com.lightbend.akka" %% "akka-projection-cassandra" % akkaProjectionVersion

Databases

• KVS for write-api.
  • Apache Cassandra
• RDMS for read-api
  • Amazon Aurora Postgresql