Admission webhook observability

[dweber019]

Is there an existing issue for this?

• I have searched the existing issues

Does this enhancement require public documentation?

• I have added an Acceptance Criteria item for adding and/or adjusting public documentation (if applicable)

Problem Statement

We are using the admission webhook of KIC but currently it's hard to reason about issues caused by the changes in the admission validation.
Imagine that some change in KIC would cause a lot of httproutes to fail admission validation after an update. How would we know this from a monitoring perspective.

Proposed Solution

• Add at least a log statement to KIC when an admission fails validation
• Additionally, it would be nice to have some prometheus metrics about the webhook

Additional information

No response

Acceptance Criteria

• Add INFO log when a admission is not allowed
• Add metrics about the admission webhook, like validation count (lables like success=true...)