Overview

Current project includes a Proof of concept for a generic scalable policy engine. Policy engine is based on drools with rule kjars discovery in a remote maven repository. Discovery of remote kjars is done via the drools KieScanner. KieScanner is a scanner of the maven repositories (both local and remote) used to automatically discover if there are new releases for a given KieModule and its dependencies and eventually deploy them in the KieRepository.

Policy engine Arquitecture:

The delivery of the different policy action messages are delivered at the policy engine workers as follows:

Prerequisites:

1. Rabbitmq pub/sub framework
   You can access to http://localhost:15672 with username/password guest/guest.
   You should configure rabbitmq by ip at the application properties of policyengine

docker-compose up -d broker
docker exec broker rabbitmq-plugins enable rabbitmq_management

2. A Nexus maven repository

docker-compose up -d my-nexus //like this there is a connectivity problem between policy manager container and nexus
docker run -d -p 8081:8081 -p 8082:8082 -p 8083:8083 --name my-nexus sonatype/nexus3:3.0.0

You should create a new repository named maven-group that includes the following sub repositories: central, releases & snapshots.
Extra information can be found http://codeheaven.io/using-nexus-3-as-your-repository-part-1-maven-artifacts/
You can access Nexus repository at http://localhost:8081

You should update the ip of the remote nexus maven repository at the following files:

• settings.xml
• /src/main/resources/application.properties

Local mode execution it in standalone mode:

mvn clean instal 
java -jar target/policy-engine-0.0.1-SNAPSHOT.jar 

Containerized mode:

In containerized mode there is an extra prerequisites. This consist in enabling a load balancer in front of the workers. Traefik load balancer is selected for that. You can access traefik at http://localhost:8080/dashboard/

Start Traefik load balancer

sudo service apache2 stop //Stop apache because traefik uses the port 80
docker-compose up -d reverse-proxy 

Create policyengine container(s)

docker  build -t policyengine . // build policy engine image
docker-compose up -d policyengine // Create only one worker
docker-compose up -d --scale policyengine=2  //Create a cluster of policy engine containers

Some usefull commmands for testing are:

docker image prune -a // remove all images which are not used by existing containers  
docker rm $(docker stop $(docker ps -a -q --filter ancestor=policyengine --format="{{.ID}}")) // kill all policy engine workers
docker logs policyengine_policyengine_1 --follow //read logs from a worker
docker exec -it  policyengine_policyengine_1  bash // get inside the container

License

This component is published under Apache 2.0 license. Please see the LICENSE file for more details.

Lead Developers

The following lead developers are responsible for this repository and have admin rights. They can, for example, merge pull requests.

• Eleni Fotopoulou (@elfo)
• Anastasios Zafeiropoulos (@tzafeir )