TerminatedWorkerException on creating a Python plot

[visr]

I'm trying to switch my Julia+Python project Quarto docs over to QuartoNotebookRunner.jl, but running into issues creating plots in Python cells.

I made this reproducible example repository: https://github.com/visr/qnr-plot-mwe, which also has the stacktrace in the error message.

The repo contains both a pixi and julia manifest. Pixi provides quarto, python and matplotlib. Julia provides CondaPkg, PythonCall and QuartoNotebookRunner v0.14. In the pixi.toml you can see I set JULIA_CONDAPKG_BACKEND = "Null" since pixi provides it, and pass QUARTO_JULIA_PROJECT = "$PIXI_PROJECT_ROOT" as mentioned on Discourse.

[MichaelHatherly]

Thanks for the thorough MWE @visr. Here's what I'm seeing locally when running that repo's reproducer. This was done on macOS, not Windows, so maybe that has something to do with the failure.

[visr]

Thanks for checking! I just found the problem, it has to do with openssl compatibility. Since I use JULIA_CONDAPKG_BACKEND = "Null" it is really on me to make sure things are compatible. Otherwise CondaPkg takes care of it unless you set JULIA_CONDAPKG_OPENSSL_VERSION=ignore. Based on JuliaPy/CondaPkg.jl#151 (comment) I should set it to 3.0, which unfortunately means some pretty large downgrades of Python and Quarto:

❯ pixi add openssl=3.0
✔ Added openssl=3.0

qnr-plot-mwe on  main [!] via 🐍 via ⨁
❯ pixi add matplotlib python quarto
✔ Added matplotlib >=3.9.1,<4
✔ Added python >=3.11.0,<3.12
✔ Added quarto >=1.4.557,<2

[visr]

Ah I see the highest OpenSSL version that works is 3.2, so I can at least keep using Python 3.12.

❯ pixi add openssl=3.2
✔ Added openssl=3.2

qnr-plot-mwe on  main [!?] via 🐍 via ⨁ took 2s
❯ pixi add quarto python matplotlib
✔ Added quarto >=1.6.41,<2
✔ Added python >=3.12.3,<3.13
✔ Added matplotlib >=3.9.1,<4

[MichaelHatherly]

Ah, that kind of issue. I would think we can do better with the error message the ends up being surfaced to users rather than just printing:

ERROR: QuartoNotebookRunner.Malt.TerminatedWorkerException()
Stacktrace:
  [1] unwrap_worker_result(worker::QuartoNotebookRunner.Malt.Worker, result::QuartoNotebookRunner.Malt.WorkerResult)
    @ QuartoNotebookRunner.Malt C:\ProgramData\DevDrives\.julia\packages\QuartoNotebookRunner\7Ikb9\src\Malt.jl:50
  [2] _wait_for_response(worker::QuartoNotebookRunner.Malt.Worker, msg_id::UInt64)
    @ QuartoNotebookRunner.Malt C:\ProgramData\DevDrives\.julia\packages\QuartoNotebookRunner\7Ikb9\src\Malt.jl:479