ebean-k8scache

L2 Cache support running in Kubernetes

Steps

1. Add ebean-k8scache as a dependency
2. Configure the kubernetes service name and port

Example configuration

ebean:
  cluster:
    active: true
    serviceName: my-service
    namespace: my-namespace
    podName: ${POD_NAME}
    port: 9911

The above means that ebean-k8scache will discover all the pods for my-service and join them as a cluster using port 9911.

Note: To discovery process succeed the k8s ServiceAccount must have access to request api /api/v1/namespaces/${namespace}/endpoints/${serviceName} and the Pod must expose the POD_NAME system variable to the container.

All the pods will run a L2 Cache and cache invalidation messages will be propagated to all the pods in the cluster as needed.

Configuration

As an example of configuration via code:

ContainerConfig container = new ContainerConfig();
container.setActive(true);
container.setPort(9911);
container.setServiceName("my-service");
container.setNamespace("my-namespace");
config.setPodName(System.getenv("POD_NAME"));

// On the ServerConfig of the default Server
// set the ContainerConfig
ServerConfig serverConfig = new ServerConfig();
serverConfig.setContainerConfig(container);


// When the container of the default starts it will discover
// the other pods and join them as a cluster 
EbeanServer defaultServer = EbeanServerFactory.create(serverConfig);

Runtime membership checking

Periodically the membership of the cluster is checked. By default this is done every minute and back off to every 5 minutes.

Logging

Set logging on io.ebean.cluster.K8s to DEBUG or TRACE for this plugin.

Set logging on io.ebean.cache to DEBUG or TRACE to view L2 cache activity such as GETs, PUTs etc.