kyma-listener

README

Kyma Listener

Listener component that listens to events sent by the Kyma watcher component.

Overview

The listener module is typically used with operators built using kube-builder but its use is not resticted only to that.

Use

1. For operators built using the kube-builder framework, you might leverage your SetupWithManager() method to initialize the listener by calling RegisterListenerComponent().

2. You might also setup your controller to watch for changes sent through the source.Channel{} returned by the listener component and react to them calling the (blder *Builder) Watches() method and providing your handler.EventHandler implementation.

3. The last step is to start the listener, which is accomplished by adding the listener as a runnable to your controller-manager. This is done by calling mgr.Add() and passing the listener returned by RegisterListenerComponent().

Sample code

    //register listener component
	runnableListener, eventChannel := listener.RegisterListenerComponent(listenerAddr, strings.ToLower(v1alpha1.KymaKind))

	//watch event channel
	controllerBuilder.Watches(eventChannel, &handler.EnqueueRequestForObject{})
	
    //start listener as a manager runnable
	mgr.Add(runnableListener)