Akka Cluster example in groovy / java

Overwiev

It shows how to create an Akka cluster in groovy / java. You can start unlimited number of server nodes and clients. However you need at least 2 seed server nodes (see below how to start them).

It’s configured to run on localhost by default. If you want to test it over network just setup IP addresses / names correctly in application.conf and MainClusterClient (there is config string ;) ). Do not forget to turn off firewalls or open needed ports (e.g. 2551 and 2552 for seed nodes).

Modules

1. cluster-common - contains actors and messages
2. cluster-master - server provides services
3. cluster-client - connects to server

How to build

You need gradle in version 1.10 and Java 7 Run

gradle build

How to run

Each server and client part can be run multiple times to simulate multiple server nodes in cluster and clients.

How to run server

Goto folder cluster-master and run

gradle run -Pmaster

It’ll start node as master seed node. To start second seed node run:

gradle run -Pslave

To run more work nodes just type

gradle run

App arguments

---

• Start node as first seed node (you need at least one instance)

-Pmaster

• Start node as second seed node (you need at least one instance)

-Pslave

• Set the node to greeter type. It means it will react only to Greating messages. Without nodeType parameter it will be set to calculator type (Calculate messages).

-PnodeType=greeter

How to run client

Go to folder cluster-client and run

gradle run

It will start client node as calculator type and start sending Calculate messages to cluster.

To run client as greeter type just run

gradle run -PclientType=greeter