Exec calls

[diegodelemos]

Whenever I try to open an exec call I get:

{
  "kind":"Status",
  "apiVersion":"v1",
  "metadata":{},
  "status":"Failure",
  "message":"Upgrade request required",
  "reason":"BadRequest","code":400
}

Which is related with the fact that requests is not SPDY compatible. Are you going to support this kind of requests in the near future?

[mbohlool]

cc @caesarxuchao

[mbohlool]

realted: http://stackoverflow.com/questions/37349440/upgrade-request-required-when-running-exec-in-kubernetes

I guess if we change code generator to accept headers, it should be possible to pass upgrade headers to the call.

Update: Look like we need an SPDY client for python too.

[diegodelemos]

Is it feasible to have it soon? It would be nice to have a date in order to know if I can use it within my deadline. If not, do you have some workaround in mind? Thank you in advance.

[mbohlool]

I don't have a date yet, the problem is urllib3 does not support SPDY protocol. we need to use something like python-spdylay. Unless somebody own this (or I found the time to look at it in more depth) I can't put a date on it.

[mbohlool]

Just spend a little more time with python-spdylay. Even their client example is not working and it does not seem to be actively developed/supported. If anybody have any idea of how to talk SPDY in python, please let me know.

[mbohlool]

More information here: kubernetes/kubernetes#24668

[diegodelemos]

Moreover, there is kubernetes/kubernetes#7452 which stands that SPDY is deprecated and HTTP/2 might be the right option, but looks like it is still hanging in the air. Anyways, it is SPDY what is working for current versions so we need to somehow find a workaround.

[mbohlool]

A little more digging pointed me to a library called thor. I will give it a try. If you can try it too to see if you can establish a SPDY connection with it, that would be nice. My assumption is SPDY is always secure so there should be a way to specify client-cert and other cert files that we normally set in kubernetes.client.configuration class.

[sebgoa]

You can do exec over websockets instead of SPDY. So would be good to investigate websockets instead of the sdpy route (which will be osbolete anyway).

[mbohlool]

Thanks @sebgoa it look like websockets are supported as a fall-back: https://github.com/kubernetes/kubernetes/blob/master/docs/devel/api-conventions.md#websockets-and-spdy

[mrmcmuffinz]

@mbohlool is there an example that you could provide demonstrating the use of exec via websockets?

[mbohlool]

@mrmcmuffinz I did not have time to do it. That is why I added "Help needed" to this issue so somebody from the community hopefully help.

[mrmcmuffinz]

@mbohlool My apologies, I thought you had some example. Do you happen to know who we can talk to, to help out? Can we work out defining what exactly it takes to get this done?

[mrmcmuffinz]

Adding my stackoverflow question here too, for other people who stumble across this. Also has anyone looked into speaking with the developers of urilib3 to see if they will support http/2? That way there is a minimum impact to the api_client...