Jupyter notebook : Server Error while accessing notebooks

Question

I'm facing the following error while trying to upload or access any file in my Jupyter notebook. NOTE: I'm using an Ubuntu 18.04 VM and Jupyter Notebook 5.7.4.

Server error: Traceback (most recent call last): File "/home/abhi1507/anaconda3/lib/python3.7/site-packages/tornado/web.py", line 1592, in _execute result = yield result File "/home/abhi1507/anaconda3/lib/python3.7/site-packages/tornado/gen.py", line 1133, in run value = future.result() File "/home/abhi1507/anaconda3/lib/python3.7/site-packages/tornado/gen.py", line 326, in wrapper yielded = next(result) File "/home/abhi1507/anaconda3/lib/python3.7/site-packages/notebook/services/contents/handlers.py", line 112, in get path=path, type=type, format=format, content=content, File "/home/abhi1507/anaconda3/lib/python3.7/site-packages/notebook/services/contents/filemanager.py", line 431, in get model = self._dir_model(path, content=content) File "/home/abhi1507/anaconda3/lib/python3.7/site-packages/notebook/services/contents/filemanager.py", line 337, in _dir_model if self.should_list(name) and not is_file_hidden(os_path, stat_res=st): File "/home/abhi1507/anaconda3/lib/python3.7/site-packages/notebook/utils.py", line 146, in is_file_hidden_posix stat_res = os.stat(abs_path) OSError: [Errno 40] Too many levels of symbolic links: '/home/abhi1507/q3.sh' AD

Answer 1

Not sure if it is the same thing, but I suddenly had all my jupyter notebooks in new conda environments start breaking today. Eventually found this worked:

pip uninstall tornado
pip install tornado==5.1.1

Jupyter Notebooks and Tornado both released new versions in the past week (circa 2019-03-01) - I think one or both is the problem. If tornado doesn't work, I'd try the same idea but downgrading jupyter (or both).

Edit: Actual cause/fix described here. Can fix the issue by updating nbconvert to v5.4.1:

pip install --upgrade nbconvert