Add hostIP to merge key for containers and ephemeralContainer ports

[jpbetz]

What type of PR is this?

Add hostIP to merge keys for server side apply operations involving container or ephemeralContainer ports to align merge keys with validation.

/kind bug

Special notes for your reviewer:

Field	validation	old merge keys	new merge keys
Container.Ports	name (if present) & {hostPort, protocol, hostIP}	containerPort, protocol	hostPort, protocol, hostIP
EphemeralContainerCommon.Ports	name (if present) & {hostPort, protocol, hostIP}	containerPort, protocol	hostPort, protocol, hostIP
ServiceSpec.Ports	name (name is required if multiple ports exist)	port, protocol	name

InitContainers already has hostIP correctly included in the set of merge keys and does not need to be updated.

The re-keying of a type requires special review for all the possible skew cases.

Does this PR introduce a user-facing change?

Fix handling of server side apply operations involving container or ephemeralContainer ports with identical port number and protocol to succeed so long as hostIP differs.

/sig api-machinery

[jpbetz]

/hold
Until we have confidence that the skew cases will exhibit sane behavior.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: jpbetz
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• api/OWNERS
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• staging/src/k8s.io/api/OWNERS
• staging/src/k8s.io/client-go/applyconfigurations/OWNERS [jpbetz]

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[jpbetz]

@apelisse Do we have tests or any other form of evidence that adding an optional field to an existing set of merge keys is safe? I've been starting to reason about it and am not 100% convinced it is safe.

[k8s-ci-robot]

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

Test name	Commit	Details	Required	Rerun command
pull-kubernetes-integration	a6fc5c2	link	true	/test pull-kubernetes-integration
pull-kubernetes-e2e-kind-ipv6	a6fc5c2	link	true	/test pull-kubernetes-e2e-kind-ipv6
pull-kubernetes-e2e-kind	a6fc5c2	link	true	/test pull-kubernetes-e2e-kind
pull-kubernetes-e2e-gce	a6fc5c2	link	true	/test pull-kubernetes-e2e-gce

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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[jpbetz]

This won't work because the {hostPort, protocol, hostIP} fields are only checked for uniqueness if hostIP is set.

[alexzielenski]

/triage accepted