set kubernetes context from tiltfile

[nicks]

Describe the Feature You Want

Your tiltfile should be able to specify which kubernetes context to switch to.

e.g.,

k8s_context('minikube')

If you edit the k8s_context call in the tiltfile during a tilt session, tilt should disconnect from that cluster and re-connect to the new one.

Why Do You Want This?

This would be a genuinely useful feature on its own! But we also expect this to be a prerequisite for a number of other cluster-management features, like

• onboarding flows that help you setup a cluster
• diagnosing a broken cluster
• resetting a cluster

Additional context

Here are some related issues that get at the same thing:
#1113 (Set the default namespace you're deploying to)
#2123 (reload the kubeconfig when the context changes)
#3791 (set up the kubeconfig during tiltfile initialization)
#3066 (don't connect to kubernetes until you need it)

[nzagorsky]

Up for this. That might help to have multiple tilt instances running at once (on top of TILT_PORT env var). Some flexibility here would be greatly appreciated.

[cmoulliard]

We should have the possibility to pass the config yaml file as we can do with kubectl with this parameter --kubeconfig='': Path to the kubeconfig file to use for CLI requests.

[nicks]

@cmoulliard if you set the KUBECONFIG env variable, I believe tilt will respect that