[test] Create integration test for exposing metrics to prometheus

[llowinge]

This is basic test scenario covering https://issues.redhat.com/browse/ENTESB-13667.

Release Note

NONE

[llowinge]

@astefanutti please review

[llowinge]

@astefanutti Shouldn't i use oc client instead of kubectl ? (i'm not sure if the Prometheus monitoring is also in plain Kubernetes). If so, should i also change the way how the tests are triggered by the automation ? Because they should run only on openshift then (now they run as part of kubernetes github action).

[llowinge]

@astefanutti Any idea how we could keep this up to date ?

[astefanutti]

@astefanutti Shouldn't i use oc client instead of kubectl ? (i'm not sure if the Prometheus monitoring is also in plain Kubernetes). If so, should i also change the way how the tests are triggered by the automation ? Because they should run only on openshift then (now they run as part of kubernetes github action).

The Prometheus trait also works with vanilla Kubernetes, so it should ideally be tested also. The assertions will probably have to be different, as for vanilla Kubernetes Thanos is not a pre-requisite.

It is fine to use kubectl even on OpenShift. Both oc and kubectl can be used interchangeably (except for oc specific commands), but one may chose to use oc for OpenShift environment for consistency purpose.

[astefanutti]

Ideally the tests would not depend on Jitpack. Unfortunately, the service bean has to be compiled beforehand and provided as an external bean archive JAR, so it has to be served from a Maven repository.

[llowinge]

@astefanutti Do you know why the travis failed ?

[astefanutti]

@llowinge I've restarted the tests. It failed because of a connection timeout.

[astefanutti]

Thanks!