list notebooks on a remote machine

list_notebooks.py

"""
William La Cava 2020
license: GPL v3
this script connects to a server via ssh, looks for running
jupyter notebooks, and lists them.

note: for this to work, ssh needs to find the jupyter command on your
remote machine. if you have jupyter in /home/you/anaconda3/bin/,
for example, you can symlink it to /usr/local/bin to achive this:
ln -s /home/you/anaconda3/bin/jupyter /usr/local/bin/

in addition, you should have jupyter configured on the host to listen on the
network (0.0.0.0) instead of 'localhost'. That way you can connect without
port forwarding. Read more:
https://lerner.co.il/2017/02/01/five-minute-guide-setting-jupyter-notebook-server/
"""

import sys
import subprocess
import os

host = sys.argv[1]
response = subprocess.Popen(["ssh",host,"jupyter notebook list"],
        stdout=subprocess.PIPE)
urls = []
# get hostname from ~/.ssh/config if it exists
record_hostname = False
if ('HOME' in os.environ.keys()
    and os.path.exists(os.environ['HOME']+'/.ssh/config')
   ):
    with open(os.environ['HOME']+'/.ssh/config','r') as f:
      for line in f.readlines():
          if line.startswith('Host') and host in line:
              record_hostname = True
          elif 'HostName' in line and record_hostname:
              hostname = line.split('HostName')[-1].strip()
              break
else:
    hostname = host

# replace '0.0.0.0' with hostname
for url in response.stdout.readlines():
    url = url.decode().replace('0.0.0.0',hostname)
    urls.append(url)

print(f'listing notebooks on {hostname}')
for url in urls:
    print(url)