Support for JupyterHub 2.0

[jtpio]

Proposed change

Currently TLJH pins to jupyterhub==1.* here:

https://github.com/jupyterhub/the-littlest-jupyterhub/blob/121b4c7d8d7ec068e07e55f24ea75ce6fa0ca462/tljh/installer.py#L124

This indicates that TLJH might not be compatible with JupyterHub 2.0.

Since JupyterHub 2.0 has been out for a while, it would be interesting to see TLJH adopting it too.

Alternative options

Not sure if TLJH can support multiple versions of JupyterHub at the same time?

Who would use this feature?

Folks wanting to migrate to the latest stable JupyterHub version, and benefit from its new features and bug fixes.

(Optional): Suggest a solution

Maybe just updating to jupyterhub==2.* could be a good starting point.

[jtpio]

Maybe just updating to jupyterhub==2.* could be a good starting point.

Actually there seems to be an open PR doing just that: https://github.com/jupyterhub/the-littlest-jupyterhub/pull/777

[manics]

The actual change should be relatively easy.... the problem is doing it without inadvertently upgrading or breaking existing deployments: https://github.com/jupyterhub/the-littlest-jupyterhub/issues/724

[astrojuanlu]

Better skip to 3.0 directly? 🙂

[westurner]

• [ ] TST: Create a directory structure for migration tests between TLJH & JupyterHub major versions?

[manics]

Once we've got a proper release out we can install the last major release for testing upgrades.

[consideRatio]

We now have jupyterhub 3 in the main branch. Follow #873 for the work towards getting the release out.