How do I convert a IPython Notebook into a Python file via commandline?

I'm looking at using the *.ipynb files as the source of truth and programmatically 'compiling' them into .py files for scheduled jobs/tasks.

The only way I understand to do this is via the GUI. Is there a way to do it via command line?

If you don't want to output a Python script every time you save, or you don't want to restart the IPython kernel:

On the command line, you can use nbconvert:

$ jupyter nbconvert --to script [YOUR_NOTEBOOK].ipynb

As a bit of a hack, you can even call the above command in an IPython notebook by pre-pending ! (used for any command line argument). Inside a notebook:

!jupyter nbconvert --to script config_template.ipynb

Before --to script was added, the option was --to python or --to=python, but it was renamed in the move toward a language-agnostic notebook system.

If you want to convert all *.ipynb files from current directory to python script, you can run the command like this:

jupyter nbconvert --to script *.ipynb

Here is a quick and dirty way to extract the code from V3 or V4 ipynb without using ipython. It does not check cell types, etc.

import sys,json

f = open(sys.argv[1], 'r') #input.ipynb
j = json.load(f)
of = open(sys.argv[2], 'w') #output.py
if j["nbformat"] >=4:
        for i,cell in enumerate(j["cells"]):
                of.write("#cell "+str(i)+"\n")
                for line in cell["source"]:
                        of.write(line)
                of.write('\n\n')
else:
        for i,cell in enumerate(j["worksheets"][0]["cells"]):
                of.write("#cell "+str(i)+"\n")
                for line in cell["input"]:
                        of.write(line)
                of.write('\n\n')

of.close()