confusing error when deploying a k8s charm to a machine model

[Kevin W Monroe]

Deploying a k8s charm to a machine model gives a confusing error:

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$ juju version
3.5.1-genericlinux-amd64

$ juju status
Model Controller Cloud/Region Version SLA Timestamp
t1 aws-us-west-2 aws/us-west-2 3.5.1 unsupported 22:00:16-05:00

Model "admin/t1" is empty.

$ juju deploy nvidia-gpu-operator --channel 1.29/stable
ERROR Charm feature requirements cannot be met:
  - charm requires feature "k8s-api" but model does not support it

Feature descriptions:
  - "k8s-api": the Kubernetes API lets charms query and manipulate the state of API objects in a Kubernetes cluster

For additional information please see: https://juju.is/docs/olm/supported-features
ERROR failed to deploy charm "nvidia-gpu-operator"
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It's not obvious to me that this is happening because i'm trying to deploy a k8s charm to a machine model. Could we clarify "charm requires feature "k8s-api" but model does not support it" so it's more clear that there's a model/charm mismatch here?

[Jordan Barrett (barrettj12)]

The relevant code is in core/assumes
https://github.com/juju/juju/tree/3.5/core/assumes

I agree it's not very user-friendly, even though an attempt was made. "Features" are an abstraction that don't exist outside Juju, and so our client facing error messages should not mention them.