ManagedKubernetesClient configuration policy should be REQUIRE

Describe the bug

ManagedKubernetesClient does not handle activate( ) method being called with null properties. The Configuration policy should be set to ‘REQUIRE’ in order to only activate when a config is present.

Fabric8 Kubernetes Client version

5.5.0

Steps to reproduce

1. Deploy kubernetes-client in osgi w/o a config file
2. Observe NPE

Caused by: java.lang.NullPointerException
	at io.fabric8.kubernetes.client.osgi.ManagedKubernetesClient.activate(ManagedKubernetesClient.java:143) ~[kubernetes-client-5.3.1-bundle.jar:?]
	... 73 more

Expected behavior

Do not try to activate a ManagedKubernetesClient without a configuration file

Runtime

Kubernetes (vanilla)

Kubernetes API Server version

1.20.12

Environment

macOS

Fabric8 Kubernetes Client Logs

No response

Additional context

No response

[rohanKanojia]

@mattrpav : You don’t have to worry about OpenShift. I will fix that as part of #3864

My question is regarding your OSGI project setup in ManagedKubernetesClient (any rough code snippet would be super helpful). I can replicate that onto OpenShift. Could you please review my reproducer to see if’s trying to reproduce correctly https://github.com/rohankanojia-forks/kubernetes-client-osgi-demo/blob/main/src/main/java/org/eclipse/jkube/quickstart/karaf/K8sBookGenerator.java#L42?

[mattrpav]

@rohanKanojia I don’t use OpenShift, so not sure how it’ll behave.

I’m happy to test out 6.x-- it’ll be a bit later this week. I’ve got 3 other oss fixes in the queue.