Show Kubernetes logs to the user while starting the pod

[elgalu]

Having a loading spinner is ok:

However showing the user what's going on, i.e. by showing K8s events for example, would work like the mirror in the elevators, users won't suffer the wait as they see some punctual progress.

[yuvipanda]

Indeed, it's a great idea! Am unsure how we can do this, though. @minrk thoughts?

…

On Mon, Mar 19, 2018 at 2:41 PM, Leo Gallucci ***@***.***> wrote: Having a loading spinner is ok: [image: screen shot 2018-03-19 at 22 38 58] <https://user-images.githubusercontent.com/111569/37623857-68e59d74-2bc6-11e8-90a0-97caec0f1dcd.png> However showing the user what's going on, i.e. by showing K8s events for example, would work like the mirror in the elevators, users won't suffer the wait as they see some punctual progress. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#148>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAB23ncwQnyQucUVlzVwbUgNIjFvTg91ks5tgCYCgaJpZM4Sw85-> .

-- Yuvi Panda T http://yuvi.in/blog

[minrk]

That would be cool. We'd need to figure out how to make the API for progress. Maybe allow Spawner.start to be an async generator yielding event messages?

[clkao]

maybe the reflector can get those events, and kubespawner provide some kind of spawn status details to be rendered by jupyterhub?

somewhat related to #141

[minrk]

Getting the data into kubespawner is definitely necessary, but the hard part is the JupyterHub side where we need to come up with a universal generic API for all spawners to use. One option is to follow the BinderHub example and use a full-blown xterm.js log. That's surely the most powerful option, but I think it's huge overkill for JupyterHub, so I'd rather do something much simpler and allow yielding updates to a staged progress bar. Something like:

{
  'message': 'text',
  'progress': 80, # out of 100
}

where a single message will be displayed and can be updated at any point and a progress bar will be filled:

[minrk]

jupyterhub/jupyterhub#1771 implements an API for Spawners to log progress and events

[elgalu]

I'm testing the kubespawner and jupyterhub master branches today and wow!

I also tried the new c.KubeSpawner.profile_list and in this case requested more CPU than any node can provide to see what happens (see screenshot)

It would be nice to see the K8s events, in this case the user would see:

Warning   FailedScheduling
0/1 nodes are available: 1 Insufficient cpu

But this looks already so nice, thank you so much!!!

[clkao]

@elgalu check out #153 that adds the k8s events