Using environment variable in jupyter_notebook_config.py - jupyter-notebook

Question

I want to use an environment variable as the location for the c.NotebookApp.notebook_dir parameter in jupyter_notebook_config.py but I have added
c.NotebookApp.notebook_dir = $JUPYTER_NOTEBOOKS
I have also created the variable
>export JUPYTER_NOTEBOOKS=/home/jupyter
but when I run Jupyter notebook I get the below error message and I can tell its not pulling the value of the variable and is trying to use the variable as a literal. Has anyone used environment variables successfully in jupyter notebook config?
[E 20:45:04.513 NotebookApp] Exception while loading config file /root/.jupyter/jupyter_notebook_config.py
Traceback (most recent call last):
File "/usr/local/lib/python3.6/site-packages/traitlets/config/application.py", line 562, in _load_config_files
config = loader.load_config()
File "/usr/local/lib/python3.6/site-packages/traitlets/config/loader.py", line 457, in load_config
self._read_file_as_dict()
File "/usr/local/lib/python3.6/site-packages/traitlets/config/loader.py", line 489, in _read_file_as_dict
py3compat.execfile(conf_filename, namespace)
File "/usr/local/lib/python3.6/site-packages/ipython_genutils/py3compat.py", line 198, in execfile
exec(compiler(f.read(), fname, 'exec'), glob, loc)
File "/root/.jupyter/jupyter_notebook_config.py", line 766
c.NotebookApp.notebook_dir = $JUPYTER_NOTEBOOKS
^
SyntaxError: unexpected character after line continuation character
[I 20:45:04.523 NotebookApp] Writing notebook server cookie secret to /root/.local/share/jupyter/runtime/notebook_cookie_secret
Traceback (most recent call last):
File "/usr/local/bin/jupyter-notebook", line 11, in <module>
sys.exit(main())
File "/usr/local/lib/python3.6/site-packages/jupyter_core/application.py", line 266, in launch_instance
return super(JupyterApp, cls).launch_instance(argv=argv, **kwargs)
File "/usr/local/lib/python3.6/site-packages/traitlets/config/application.py", line 657, in launch_instance
app.initialize(argv)
File "</usr/local/lib/python3.6/site-packages/decorator.py:decorator-gen-7>", line 2, in initialize
File "/usr/local/lib/python3.6/site-packages/traitlets/config/application.py", line 87, in catch_config_error
return method(app, *args, **kwargs)
File "/usr/local/lib/python3.6/site-packages/notebook/notebookapp.py", line 1628, in initialize
self.init_webapp()
File "/usr/local/lib/python3.6/site-packages/notebook/notebookapp.py", line 1407, in init_webapp
self.http_server.listen(port, self.ip)
File "/usr/local/lib/python3.6/site-packages/tornado/tcpserver.py", line 151, in listen
sockets = bind_sockets(port, address=address)
File "/usr/local/lib/python3.6/site-packages/tornado/netutil.py", line 174, in bind_sockets
sock.bind(sockaddr)
OSError: [Errno 99] Cannot assign requested address

Answer 1

It isn't clear that you are using environment variables properly. I glanced at the docs and it looks like %env JUPYTER_NOTEBOOKS is the right way to do it. I checked this on my local system and it works (for a different env variable). Give that a try - good luck! :-) . Below are the docs.
https://ipython.readthedocs.io/en/stable/interactive/magics.html#magic-env

Answer 2

Thanks jimf your link helped. I was able to get things working because I was NOT using environment variables correctly. Instead of modifying the .py file I added the parameter to my command of starting jupyter notebook like this:
--NotebookApp.notebook_dir=$JUPYTER_NOTEBOOKS
I was then able to change the variable value and change where jupyter was looking for notebooks.

Answer 3

You can make use of environment variables in the jupyter_notebook_config.py file, but note that the file is a Python file, so (as you already figured out) bash syntax won't work. Instead you can use Python syntax. You can actually write any Python code you like in this file, so this would be valid syntax:
import os
c.NotebookApp.notebook_dir=os.getenv('JUPYTER_NOTEBOOKS')
This would allow you to do even more complex things if you needed.