Kernel not starting in JupyterLab but works fine in Jupyter Notebook

[manu080797]

I'm trying to run the Wolfram Engine in JupyterLab in macOS Mojave but the kernel never starts. Running "Jupyter notebook" the kernel starts and everything works fine. However when attempting the same in "jupyter-lab" the Wolfram Engine does not start and the kernel times out. The only warning I get in the console where Jupyter is running is:

 args::shdw: Symbol args appears in multiple contexts 
    {WolframLanguageForJupyter`, Global`}; definitions in context 
    WolframLanguageForJupyter` may shadow or be shadowed by other definitions.

but I get the same message in both JupyterLab and Jupyter notebook.

Software version:

macOS Mojave 10.14.6
Python 3.6.9 | Anaconda, Inc. | (default, Jul 30 2019, 13:42:17) 
GCC 4.2.1 Compatible Clang 4.0.1 (tags/RELEASE_401/final)
Jupyter Notebook Server - version 6.0.1
Jupyter Lab - version 1.1.4
Wolfram Language For Jupyter 0.9.1
Wolfram Language 12.0.0 Engine for Mac OS X x86 (64-bit)

[cc-wr]

Some problems exist with JupyterLab for older versions of this project (e.g., the initial GitHub release). Can you give me more details on how you installed the project?

[manu080797]

I downloaded the repo in zip format and extracted it in Downloads folder. I installed Wolfram Engine 12. Then cd into ~/Downloads/WolframLanguageForJupyter-0.9.1 folder. Finally run: wolframscript configure-jupyter.wls add

[cc-wr]

Okay, thank you.

I have an additional question: with JupyterLab, do you run the Wolfram Language under a notebook or under a console?

[manu080797]

Either way fails, but works perfectly in Jupyter notebook. I have updated all my packages in the python environment and reinstalled (remove then add) Wolfram Language For Jupyter 0.9.1 with the procedure described above. I get the same behavior in the updated environment. Later, I will try installing the kernel in a python 3.7 environment to see if anything changes. Can you reproduce the bug?

[cc-wr]

Can you reproduce the bug?

I have not been able to yet, but I am still trying to.

[maresb]

Running from the base-notebook Jupyter Docker stack, I installed WolframLanguageForJupyter from the Paclet. Jupyter Notebook works, but in JupyterLab I get the following:

[I 00:48:19.419 LabApp] Creating new notebook in /
[I 00:48:20.071 LabApp] Kernel started: c78ef30d-658c-4cfb-986a-c750d515ca32
No valid password found.
[I 00:48:23.070 LabApp] KernelRestarter: restarting kernel (1/5), new random ports
No valid password found.
[I 00:48:26.080 LabApp] KernelRestarter: restarting kernel (2/5), new random ports
No valid password found.
[I 00:48:29.088 LabApp] KernelRestarter: restarting kernel (3/5), new random ports
No valid password found.
[I 00:48:32.096 LabApp] KernelRestarter: restarting kernel (4/5), new random ports
No valid password found.
[W 00:48:35.104 LabApp] KernelRestarter: restart failed
[W 00:48:35.104 LabApp] Kernel c78ef30d-658c-4cfb-986a-c750d515ca32 died, removing from map.

[PhyX-Meow]

Now it works well with me. (Windows10, jupyterlab1.2.6) But inside jupyterlab, console with mma12 kernel still not works, and give out an error: "Error in getting kernel banner"

[PhyX-Meow]

It works in jupyterlab console, I just should try an "1+1", the only thing is the kernel banner has error being fetched. I think this issue could be closed @manu080797

[LEXUGE]

This could be caused that WolframKernel cannot find mathpass under your home directory.