Add nbconvert[qtpdf] and nbconvert[webpdf] to UToronto image

[jmunroe]

Reference: https://2i2c.freshdesk.com/a/tickets/2830

In Jupyter classic, when a client selects the menu option File -> Download as, I see two options "PDF via HTML". Both of them lead to "Internal Server Errors".

One reports: "nbconvert failed: PyQtWebEngine is not installed to support Qt PDF conversion. Please install nbconvert[qtpdf] to enable."

The other reports: "nbconvert failed: Playwright is not installed to support Web PDF conversion. Please install nbconvert[webpdf] to enable."

Can you please install the necessary packages on the image? Thanks!

[jmunroe]

This came through Freshdesk a few weeks ago and should have been picked up in our Iteration 11 planning as a support task.

[jnywong]

I started some work on this after staff access to the hub was configured in #5545 .

Here is the draft PR for anyone who has capacity to pick up in the current iteration.

I would estimate the effort as more of a 2 or even 3, since installing playwright and pyqtengine for JHub is not straightforward.

[sgibson91]

@jnywong I don't think you actually linked your PR above?

ETA: It's 2i2c-org/utoronto-image#63

[jnywong]

Oo yep you're right, I updated the comment above. Ty Sarah!

[sgibson91]

I have made some progress: The image build now succeeds in CI and exporting to PDF via LaTeX now works.

I'm still struggling with webpdf. I still see the "Please install nbconvert[webpdf]" error even though I am now explicitly installing webpdf. This error also seems to be fatal in the sense that it kills the server, as the notebook warns about being disconnected from the kernel.

Also weirdly, in the "File > Download as" menu, there are two "Pdf via HTML" options, and I don't know what is causing it but suspect it will cause a point of confusion for this community.

Overall, I think this task is beginning to look like an 8 effort or higher.

[sgibson91]

Can't authenticate a socket?

[W 2025-03-14 13:55:54.622 ServerApp] Couldn't authenticate WebSocket connection
[W 2025-03-14 13:55:54.631 ServerApp] 403 GET /user/sgibson@2i2c.org/api/kernels/438bb7c4-0370-4616-a0fe-7d885bc54fda/channels?session_id=c928835792c04f1e9c8c50995b968e43 (@10.1.0.23) 9.69ms

[sgibson91]

A different error, but this is from the second "File > Download as > PDF via HTML" option. So this will definitely be confusing for users if they're going to produce different errors.

nbconvert failed: No suitable chromium executable found on the system. Please use '--allow-chromium-download' to allow downloading one,or install it using `playwright install chromium`.

[agoose77]

I can take a look at this today, probably, if you want a second pair of eyes.

[sgibson91]

Would appreciate that, I think my eyes are becoming less reliable

[jnywong]

Fwiw, I also ran into this litany of problems! hug