Corrupted URL when upgraded to Jupyter Notebook version 7.0.0rc0 and Jupyter Lab version 4.0.2

[balajialg]

Describe the bug

The URL to launch the notebook got corrupted when we upgraded the Jupyter Notebook version to 7.0.0rc0 and the Jupyter Lab version to 4.0.2 (JN version 7.0.0rc0 warranted an upgrade from 4.0.0 to 4.0.2 in Lab). When we launch the hub, it loads a URL - Hub_URL/user/xx/user/xx/user/xx/lab that repeats "user/username" thrice and as a result returns a 404 error. This has been reported by multiple users within Berkeley who tested the deployment. Previously, we had Notebook 7.0.0b3 and Lab 4.0.0 which did not have the URL corruption issue.

I am not sure whether this is a Lab specific issue or a notebook-specific issue. Please redirect me to the right repository if I am mistaken here. @ryanlovett

To Reproduce
Steps to reproduce the behavior:

1. Upgrade Notebook to 7.0.0rc0
2. Upgrade Lab to 4.0.2
3. Try launching the hub
4. See 404 error because of URL getting corrupted

Expected behavior
Notebook should launch without any URL corruption issues

Screenshots

Desktop (please complete the following information):

• OS: Windows/Mac
• Browser: Firefox/Safari

Additional context
Add any other context about the problem here.

[jtpio]

Many thanks @balajialg for trying the rc and reporting the issue 👍

This change might be related since it realigned how the JupyterHub config was handled with what JupyterLab does: #6918

Not sure yet but maybe it's related.

If you are able to try with 7.0.0b4 then we could see if this is an issue with 7.0.0rc0 only.

[balajialg]

@jtpio Happy to help! I will definitely test 7.0.0b4 version and report the results here.

[balajialg]

@jtpio Based on the initial investigation done by @ryanlovett and myself, the error seems to persist even after downgrading to notebook version 7.0.0b4. We tried to check whether it was due to lab's version and downgraded lab to 4.0.1 and the error persisted. We also tried to downgrade the lab to 4.0.0 but the build failed with the following error,

The conflict is caused by:
    The user requested jupyterlab==4.0.0
    notebook 7.0.0b4 depends on jupyterlab<5 and >=4.0.1

However, everything seems to work well with the notebook 7.0.0b3 and Lab 4.0.0

[jtpio]

Thanks @balajialg for the input.

Then looking at the 7.0.0b4 changelog it could be because of this change #6899.

[jtpio]

FYI @balajialg 7.0.0rc1 is released: https://github.com/jupyter/notebook/releases/tag/v7.0.0rc1

Let us know if that fixes the issue, thanks!

[jtpio]

Just opened berkeley-dsep-infra/datahub#4671

[balajialg]

That's great. Thanks @jtpio! We will test rc1 and give you an update wrt resolution!

[balajialg]

@jtpio Upgrade to rc1 seems to have fixed the issue for me. I will let @ryanlovett also test the deployment and confirm my report. Thanks a lot for the quick fix!

[ryanlovett]

@balajialg Confirmed!

[jtpio]

Nice, thanks @balajialg and @ryanlovett for checking!