Can't start kernel on 4.0.5

[trungleduc]

Description

I can't start the kernel and get 404 on this request http://127.0.0.1:5445/xeus/xeus-kernels/libxeus.so

Reproduce

1. Create new env

mamba create -n xeus-bug python=3.13 jupyterlite jupyterlite-xeus

2. Create environment.yml file

name: xeus-kernels
channels:
  - https://prefix.dev/emscripten-forge-dev
  - https://prefix.dev/conda-forge
dependencies:
  - xeus-python

3. Build and serve JupyterLite

jupyter lite build  --output-dir _output
python -m http.server 5445 --directory _output

4. Go to http://127.0.0.1:5444/ and start a kernel

Expected behavior

I can start a kernel

Context

jupyterlite               0.6.2              pyhe01879c_0    conda-forge
jupyterlite-core          0.6.2              pyhe01879c_0    conda-forge
jupyterlite-xeus          4.0.5              pyhd8ed1ab_0    conda-forge

[trungleduc]

pinning xeus-python back to 0.17.4=py313h027658c_2 make it work

[martinRenou]

@JohanMabille @anutosh491 can you think of something? The new xeus python build hasn't changed much apart from some Python dependency. Should we pin xeus in the xeus-python recipe?

[jtpio]

Also noticed this issue when updating the try jupyter deployment with an unrelated change: jupyter/try-jupyter#67 (the xeus packages would need a pin)

[anutosh491]

can you think of something?

Xeus shared build was only available after 5.2.3 (and xeus-lite started using this shared build from 4.0.0)

So xeus-python should work with a combination of xeus 5.2.2 and xeus-lite 3.2.1

Updating xeus-python to the shared xeus build, would also not be too challenging (but needs to be accompanied with a release)

So yeah can pin if the above is not planned.

[martinRenou]

Shouldn't those releases of xeus and xeus-lite be major releases?

[martinRenou]

emscripten-forge/recipes#2484

[martinRenou]

@trungleduc @jtpio it seems to work again with the latest build!

[martinRenou]

Updating xeus-python to the shared xeus build, would also not be too challenging (but needs to be accompanied with a release)

@anutosh491 would you be able to help on this?

[anutosh491]

Doing it soon !

[trungleduc]

Great! thanks all!

[martinRenou]

@anutosh491 I'm worried that other kernels will be impacted too. Which kernels have been updated so far? Should we pin xeus and xeus-lite in all of them?

[anutosh491]

I'm worried that other kernels will be impacted too. Which kernels have been updated so far? Should we pin xeus and xeus-lite in all of them?

Its only xeus-cpp that has been using the latest xeus.

Here's my PR on xeus-python : jupyter-xeus/xeus-python#657

Probably xeus-r, xeus-lua, xeus-sqlite need similar PRs