Trial name could not be passed to env

[alexeygorobets]

/kind bug

What steps did you take and what happened:
I am trying to get access to the trial name from the trial's pod (I need it to build S3 bucket path for trained model).
I follow this example.
But I've got an error

Error from server: error when creating "trial-metadata-substitution.yaml": admission webhook "validator.experiment.katib.kubeflow.org" denied the request: parameter reference ${trialSpec.Name} does not exist in spec.parameters: [{lr double {0.03 0.01 [] }}]

This example itself does not work.

What did you expect to happen:
Trials running with env TRIAL_NAME resolved as trail's name.

Anything else you would like to add:
This example was working on Katib 0.12.0.
It looks like additional check added in this PR might cause this issue. One of the resolution might be to skip this check here if it's trial metadata (such as name, kind, apiversion etc.).

But I will be happy with any other solution which allows me to pass trial name to pod as environment variable.

Environment:

• Katib version (check the Katib controller image version): 0.13.0
• Kubernetes version: 1.22
• OS : CentOS

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[wenxinax]

same problem...

[johnugeorge]

This needs to be fixed for the next release.

[johnugeorge]

Validation added in #1726 needs to be extended to substitutions as well

[johnugeorge]

/cc @henrysecond1

[henrysecond1]

I'm sorry that I didn't consider the parameter substitution case.

As @alexeygorobets said, I think we can skip parameter reference checking when it's a trial metadata. Please let me know if there's anything I can help with.

[johnugeorge]

Instead of skipping metadata, we can validate the metadata fields.

We need to move the some of the validations from https://github.com/kubeflow/katib/blob/master/pkg/controller.v1beta1/experiment/manifest/generator.go#L123 to verify fields