Tab completion should also look at the Kargo API

[christianh814]

Checklist

• I've searched the issue queue to verify this is not a duplicate feature request.
• I've pasted the output of kargo version, if applicable.
• I've pasted logs, if applicable.

Proposed Feature

When using kargo cli, the tab completion should also look at the API that the CLI auth'ed against. Similar to Kubernetes.

Currently:

$ kargo get projects kargo<TAB>
kargo/             kargo-render.yaml 

^ These are local files.

Where as in Kubernetes

$ kubectl get namespaces kargo<tab>
kargo       kargo-demo

^ Those are namespaces (what I actually want)

It would be nice if I could get this.

$ kargo get projects kargo<tab>
kargo-demo

^ tabs out to just show the current projects.

All subcommands should follow this.

Motivation

Make it act more like Kubernetes and other CLI tools.

Suggested Implementation

A good place to look is the kubectl code. Not sure what's involved

[krancour]

@christianh814 I've wanted this as well. Thanks for opening the issue.

@hiddeco or @jessesuen in case you know what's involved. I do not.

This definitely won't get into v0.6.0.

[hiddeco]

This is done through "dynamic completion" in Cobra (https://github.com/spf13/cobra/blob/v1.6.x/shell_completions.md#dynamic-completion-of-nouns).

[krancour]

@hiddeco tried that just now to satisfy my own curiosity and wasn't able to get it working. Maybe when time permits, you can show me what I am doing wrong.