feat(monitoring): Migrate to PodMonitor for Integration monitoring

[astefanutti]

Fixes #1555.
Fixes #2212.

Tested compatibility with Knative, and OpenShift monitoring stack, using the feed, splitter, printer example:

Release Note

feat(monitoring): Migrate to PodMonitor for Integration monitoring

[nicolaferraro]

May there be a general issue in the runtime? I see a NullPointerException in the logs

[astefanutti]

May there be a general issue in the runtime? I see a NullPointerException in the logs

Yes, it seems there is another issue with the polyglot tests, as well as the OpenAPI ones. It may relate to apache/camel-k-runtime#658.

@squakez would you be able to have a look, it seems for these tests, the source type may be null.

[astefanutti]

Let me merge this as the remaining CI errors are not related.

[squakez]

May there be a general issue in the runtime? I see a NullPointerException in the logs

Yes, it seems there is another issue with the polyglot tests, as well as the OpenAPI ones. It may relate to apache/camel-k-runtime#658.

@squakez would you be able to have a look, it seems for these tests, the source type may be null.

Yes, I planned to work on it soon.

[squakez]

We have too many places where we just don't set the SourceType right now in the code. For the OpenAPI, for example it's here but I've found a few more. I've provided a defensive solution for the time being in order to avoid any possible NPE but I think we need a more devised solution.

I think we should understand if we want always to set the SourceType and hence enforce it in all parts of the code here in Camel K.

I will better follow up with a separate issue.

[astefanutti]

The tactical solution sounds indeed safer as we are releasing 1.4.0. Once it's out, one approach is to set the type field as required in the Integration CRD, possibly adding the list of possible values, and fix the places where it's missing.