Should xeus-python work with Jupyter running --transport=ipc?

[rcthomas]

I had some trouble trying out the xeus-python kernel. I have a fresh Miniconda-based setup with conda-forge based JupyterLab, xeus, etc. The kernel tries to start up, and says "Connecting" for a while but then fails. In the log I see this while it's trying and re-trying:

terminate called after throwing an instance of 'zmq::error_t'
  what():  Invalid argument
Fatal Python error: Aborted

Current thread 0x00002aaaaaccd740 (most recent call first):
<no Python frame>

Then a bit later

[E 2020-12-02 20:10:17.756 SingleUserNotebookApp handlers:276] Error opening stream: HTTP 404: Not Found 
    (Kernel does not exist: 2b7f4c52-c299-4a05-9a7b-8d1ac186dddd

It occurred to me in our deployment we run with --transport=ipc so I shut that off and voila (sorry) the xeus kernel started up just fine. Is there any chance that will be supported? Thanks!

[JohanMabille]

xeus-python is supposed to support IPC, so it looks like you found a bug ;) Can you print the connection file passed to the kernel?

[rcthomas]

Connection file below. Have you perhaps been able to reproduce the issue?

{
  "shell_port": 1,
  "iopub_port": 2,
  "stdin_port": 3,
  "control_port": 4,
  "hb_port": 5,
  "ip": "/global/u1/r/rthomas/.local/share/jupyter/runtime/kernel-2b7f4c52-c299-4a05-9a7b-8d1ac186dddd-ipc",
  "key": "a0a38f01-54dcf64232f5120321a9b3a7",
  "transport": "ipc",
  "signature_scheme": "hmac-sha256",
  "kernel_name": "xpython"
}