edwardt / openkitchen-akka

Repository for openkitchen live and hands-on akka coding

Openkitchen Akka Event Sourcing Application

Application

The application is a simple webshop that is build with the following stack:

• Akka
• Spray
• AngularJS
• Twitter Bootstrap

Build and Run

With Typesafe Activator

• Execute ./bin/activator ui
• Activator is a web-ide. Write code, compile it, run tests, run the application or generate files for your favourite IDE.
• To start the application click on Run and then Start
• Open a browser using the following url: http://localhost:8080/
• From there all endpoints of the REST interface can be called using the gui

With SBT

• Execute ./bin/sbt.sh
• Type run
• Open a browser using the following url: http://localhost:8080/
• From there all endpoints of the REST interface can be called using the gui

Create Executable jar

• Execute ./bin/sbt.sh assembly. This will create an executable jar in target/scala-2.11
• Run the server as follows: java -jar xita-innovationday-assembly-<version>.jar

Test REST API manually

Note: Since it's a shopping cart the REST API is session-based. The name of the session cookie is session-id.

• Add an item to the shopping cart:

curl -b session-id=12121212 -d '{"itemId":"dell-venue"}' -H "Content-Type: application/json"  http:localhost:8080/cart

• Retrieve shopping cart contents:

curl -b session-id=12121212 http://localhost:8080/cart

• Remove an item from the shopping cart:

curl -b session-id=12121212 -X "DELETE" http://localhost:8080/cart?itemId=dell-venue

• Place order

curl -b session-id=12121212 -X "PUT" http://localhost:8080/order

##Labs ###Lab 1: git checkout lab1

• Starting point: Web UI & Spray Rest API voor shopping cart manipulations. The Carts Manager Actor and Cart Actor are not implemented
• Lab 1: Implement the com.xebia.openkitchen.cart.CartManagerActor that handles com.xebia.openkitchen.cart.CartManagerActor.Envelope messages received from the Spray route: com.xebia.openkitchen.api.Api. Per session the CartManagerActor has to create a Cart Actor. To achieve that use the Envelope's session id to create or get a Cart Actor using the Props passed as a constructor argument. The payload of the Envelope needs to be forwarded to the Cart Actor. As for now use a Dummy implementation for the Cart Actor.
• Make the following test succeed: com.xebia.openkitchen.cart.CartMangerActorSpec

###Lab 2 git checkout lab2

• Starting point: Implementation of the Carts Manager Actor (CartManagerActor). The Cart Actor is not implemented.
• Lab 2: Implement the com.xebia.openkitchen.cart.SimpleCartActor that keeps the cart data in-memory. To see which operations this Actor must support take a look at the Spray route: com.xebia.openkitchen.api.Api, which sends the payload intended for the Cart Actor wrapped in an Envelope. As mentioned in the previous lab the Cart Actor only has to handle the payload message (like com.xebia.openkitchen.cart.CartDomain.AddToCartRequest, RemoveFromCartRequest, GetCartRequest, OrderRequest) and not the whole Envelope message.
• Make the following test succeed: com.xebia.openkitchen.cart.SimpleCartActorSpec

###Lab 3 git checkout lab3

• Starting point: Implementation of an in-memory Cart Actor (SimpleCartActor)
• Lab 3: Implement the com.xebia.openkitchen.cart.PersistentCartActor, which makes use of Event Sourcing (Akka persistence) to persist all cart events.
• For testability add each succesfully persisted Event to the eventStream using the predefined publish method.
• Change the Props passed to the CartManagerActor in com.xebia.openkitchen.api.WebshopActor to return an instance of PersistentCartActor.
• Make the following tests succeed: Lab 3 of com.xebia.openkitchen.cart.PersistentCartActorSpec

###Bonus Lab 4 git checkout lab4

• Starting point: Implementation of a persistent Cart Actor (PersistentCartActor)
• Lab 4: Extend the com.xebia.openkitchen.cart.PersistentCartActor to make use of: passivation and snapshotting
• Implement a receiveTimeout (e.g. 10 seconds). Upon receival of the akka.actor.ReceiveTimeout message take a snapshot (saveSnapshot) of the current cart
• After the snapshot is saved Akka persistence sends a akka.persistence.SaveSnapshotSuccess or akka.persistence.SaveSnapshotFailure message to the actor. In both cases: set the message on the message bus for testability, then kill the actor
• When the actor recovers receiveRecover receives a akka.persistence.SnapshotOffer. Make sure it is processsed correctly
• Make the following test succeed: Bonus Lab 4 of com.xebia.openkitchen.cart.PersistentCartActorSpec

###Solution git checkout final-solution

• Final solution with the com.xebia.openkitchen.cart.PersistentCartActor that supports snapshotting en passivation