Zero-to-jupyterhub-k8s: Add support to Helm Chart for specifying hostname of GitHub Enterprise / GitLab server

[lambertjosh]

For users who have a self-hosted GitHub or GitLab instance, and want to leverage OAuth, they will need to pass along the host name. This looks to be supported by JupyterHub, but not by the Helm chart.

It would be great if this was added, or documentation recommending adding it as an extraEnv field.

[ablekh]

This feature seems to be supported by z2jh Helm chart. See this section in the _Helm Chart Configuration Reference_ page: http://zero-to-jupyterhub.readthedocs.io/en/latest/reference.html#hub-extraenv.

[lambertjosh]

@ablekh yes, we have it working, however it's not documented very clearly.

You currently have to read here to understand how to configure auth in the charts: https://zero-to-jupyterhub.readthedocs.io/en/latest/authentication.html#github

Then you have to go find the service specific instructions here: https://github.com/jupyterhub/oauthenticator#github-setup

Then you see you can configure the environment variable, at which point you need to know that you can set that using the extraEnv parameter as you mentioned.

It would be great if this was documented a little better within the Helm chart repo, or alternatively these options were added to the chart as they are probably fairly common for enterprise users.

I can take a crack at updating the docs, if that is the path that we want to go down.

[ablekh]

@lambertjosh I see now what you meant. I agree that Helm chart section of the z2jh documentation would benefit from updating it to consolidate all relevant pieces (or, at least, pointers to them) and/or expose this feature as a chart's embedded option. It would be nice, if you could try updating the docs. Thank you!

[choldgraf]

@lambertjosh we'd love to help out on a docs PR if you've got a moment to edit things in a way that'd make sense to you! Do you think you'd have the time to open a PR we can iterate on?

[consideRatio]

This is configurable through auth.gitlab.gitlabUrl, but I notice there are other things missing, such as allowed_project_ids, see here and compare with this.

In general, we should try finding a more sustainable configuration experience to avoid needing this Helm chart ot keep updated with the changes in configuration of authenticators.

[consideRatio]

Closing the issue as gitlab_url is configurable at least, and adding a note to help us get a better system in place where this doesn't happen.