[WIP] OCPBUGS-55192: Add IngressController .spec.domain validation

[grzpiotrowski]

This PR fixes OCPBUGS-55192.

Add ratcheting validation of the .spec.domain field of ingress controller.
Domain must consist of lowercase alphanumeric characters '-' or '.', and each label must start and end with an alphanumeric character.

Previously, the user could configure the .spec.domain field incorrectly which could result in the router pods entering a CrashLoopBackOff state immediately upon creation with error: invalid canonical hostname: [...].

Opted not to add the max length validation // +kubebuilder:validation:MaxLength=253 as it could be slightly misleading, because even if .spec.domain does not exceed that 253 characters limit, we could end up with an invalid canonical hostname error as this is constructed from the router name and the IC domain, which length could not be predicted here.

• operator/v1/types_ingress.go (IngressControllerSpec): Add ratcheting validation of the Domain field.
• operator/v1/tests/ingresscontrollers.operator.openshift.io/AAA_ungated.yaml Add test cases for the ingress controller .spec.domain field validation

[openshift-ci]

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[openshift-ci]

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[openshift-ci-robot]

@grzpiotrowski: This pull request references Jira Issue OCPBUGS-55192, which is invalid:

• expected the bug to target the "4.20.0" version, but no target version was set

Comment /jira refresh to re-evaluate validity if changes to the Jira bug are made, or edit the title of this pull request to link to a different bug.

The bug has been updated to refer to the pull request using the external bug tracker.

In response to this:

This PR fixes OCPBUGS-55192.

Add ratcheting validation of the .spec.domain field of ingress controller.
Domain must consist of lowercase alphanumeric characters '-' or '.', and each label must start and end with an alphanumeric character.

Previously, the user could configure the .spec.domain field incorrectly which could result in the router pods entering a CrashLoopBackOff state immediately upon creation with error: invalid canonical hostname: [...].

Opted not to add the max length validation // +kubebuilder:validation:MaxLength=253 as it could be slightly misleading, because even if .spec.domain does not exceed that 253 characters limit, we could end up with an invalid canonical hostname error as this is constructed from the router name and the IC domain, which length could not be predicted here.

• operator/v1/types_ingress.go (IngressControllerSpec): Add ratcheting validation of the Domain field.
• operator/v1/tests/ingresscontrollers.operator.openshift.io/AAA_ungated.yaml Add test cases for the ingress controller .spec.domain field validation

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[openshift-ci]

@grzpiotrowski: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/verify	d5e7974	link	true	/test verify

Full PR test history. Your PR dashboard.

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