v1alpha1.extension_repo should pull latest from specific git references

[brunoluiz]

Describe the Feature You Want

If a team wants to pin it the v1alpha1.extension_repo reference to a rolling tag (eg: v1 or main), it would be interesting if Tilt could pull latest changes on tilt up or similar.

Current Behavior

In a few cases, teams might want to pin the v1alpha1.extension_repo to a specific version and this can already be done through a specific tag or commit sha. But we observed that many want to set it to a rolling release, which currently is not possible: if set to a reference, it will pull it once and never refresh it, til a manual git pull is done.

This git pull is not documented and requires the user to navigate to the XDG folder and do pull:

cd '/Users/brunoluiz/Library/Application Support/tilt-dev/tilt_modules/github.com/brunoluiz/tilt-extensions'
git pull

Why Do You Want This?

• It would give teams choice to use rolling releases and/or tagged releases
• Less friction or debugging due to "pull once" behaviour (is not documented)

Alternatives

If nothing can be done, probably might be worth to document it and give a run-book to users on how to update references rolling references.

[nicks]

ya, i think the way we originally designed this was -

• if no tag is given, it should pull the latest branch
• if a tag is given, we assume the tag is immutable and only pull once

tilt/internal/controllers/core/extensionrepo/reconciler.go

Line 233 in ea06944

pinnedToVersion := state.spec.Ref != "" && state.spec.Ref != "HEAD"

i guess the right way to do it is to make it more like pull = 'auto' | 'always' | 'never' sort of like how kubernetes works