Labels referencing resources name can be too long

[cyriltovena]

In Kubernetes you can create a resource with a 253 characters long name :

By convention, the names of Kubernetes resources should be up to maximum length of 253 characters and consist of lower case alphanumeric characters, -, and ., but certain resources have more specific restrictions.

However labels and annotations values are restricted to 63 characters :

Valid label values must be 63 characters or less and must be empty or begin and end with an alphanumeric character ([a-z0-9A-Z]) with dashes (-), underscores (_), dots (.), and alphanumerics between.

In Agones we're setting labels value for referencing parent resources, but if a parent resource has a long name this cause errors.

References:
https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/
https://kubernetes.io/docs/concepts/overview/working-with-objects/names/

/cc @victor-prodan

[aLekSer]

This give an error here:

 "agones.dev/agones/pkg/fleets.(*Controller).upsertGameServerSet
	/go/src/agones.dev/agones/pkg/fleets/controller.go:258"

I am thinking of CreationValidationHandler on Create and Update the Fleet to check the Fleet Name length (and insist on no more than 63).

[markmandel]

Can this now be closed, or do we need to do GameServer as well?

[aLekSer]

Let me check other places were we use name in labels.
Definitely need validation of this kind in GS.

	pod.ObjectMeta.Labels[GameServerPodLabel] = gs.ObjectMeta.Name

[aLekSer]

@Kuqd I think this ticket could be closed now. All names which reside in Label covered with validation functions.