500 Error at launch (KeyError: 'terminals_available' in self.settings) #255
Description
Also reported on discourse.
macOS 13.5, Python 3.11.4 (homebrew)
With the recent move to notebook 7, I have been having issues with both notebook (documented here and here) and nbclassic.
For the latter, I am seeing a traceback, followed by a 500 error in the browser:
[E 2023-07-26 08:40:30.645 ServerApp] Uncaught exception GET /nbclassic/tree?token=e2a5e04ac6410a588e1132bac555b4f1fce1c781e1c9b4e0 (::1)
HTTPServerRequest(protocol='http', host='localhost:8888', method='GET', uri='/nbclassic/tree?token=e2a5e04ac6410a588e1132bac555b4f1fce1c781e1c9b4e0', version='HTTP/1.1', remote_ip='::1')
Traceback (most recent call last):
File "/opt/homebrew/lib/python3.11/site-packages/tornado/web.py", line 1786, in _execute
result = await result
^^^^^^^^^^^^
File "/opt/homebrew/lib/python3.11/site-packages/tornado/gen.py", line 786, in run
yielded = self.gen.send(value)
^^^^^^^^^^^^^^^^^^^^
File "/opt/homebrew/lib/python3.11/site-packages/nbclassic/tree/handlers.py", line 69, in get
terminals_available=self.settings['terminals_available'],
~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^
KeyError: 'terminals_available'
If I change "/opt/homebrew/lib/python3.11/site-packages/nbclassic/tree/handlers.py", line 69 from
terminals_available=self.settings['terminals_available'],
to
terminals_available=self.settings.get('terminals_available', False),
(as is done in notebook/app.py) it works (no errors, no 500), but I assume this shouldn't be necessary (and perhaps hides a real bug or config issue)?
I assume it is a local config issue somehow, but in fact even if I get rid of all of the current directories listed with jupyter --paths it does not seem to help.
(There seem to be other interface problems as documented in my jupyter/notebook issue. Also, if relevant: Python 3.11 is installed by homebrew, but all packages, including jupyter, notebook, etc. are installed with pip.)
Any ideas?