freedoughbro/event-stream-api

Restful Event Stream API built with Free monads

event-stream-api

Demo for Melbourne Scala User Group.

Quick Start

    ./sbt run

and to bootstrap with some data:

    cd /src/test/resources
    ./play.sh

Actions

This is a system that store deltas or events that can be replayed to represent the state of an entity. It has a REST like interface to save, retrieve and snapshot events.

Events can be streamed for downstream clients wishing to consumer events.

Here are the current actions:

• POST /event with an event body
• GET /events --> a paginated stream of events (optional params ?pageSize=10&pageNumber=1&systemName=<systemName>)
• GET /events/<enitiyId> --> a paginated stream of events for the given entity Id (optional params ?pageSize=10&pageNumber=1&systemName=<systemName>)
• GET /entity<entityId>/<systemName> --> replays the events building up the entity (optionally pass through the point in time ?at=2015-05-25T12:00:00Z)
• POST /snapshot/<entityId>/<systemName>/<time> --> Creates a snapshot for the entity at the supplied time.

Database setup

You can use the in memory mutable map by default or you can configure a postgresql database by uncommenting the following line in Main.scala:

  //private val db = new SlickDatabase("events", "events",
  //  "jdbc:postgresql://localhost/events", "org.postgresql.Driver")

  //private val eventStoreInterpreter = new SqlInterpreter(db)
  //Try(sqlInterpreter.createDDL())

and comment out:

    private val eventStoreInterpreter = new MutableMapEventStoreInterpreter()

You will need a running postgresql server with a database called events and a user called events with password events.