Is this an efficient way of mounting a file-system via SSH (SSHFS)?

Question

#!/usr/bin/python3 
# Description: Python script that will mount FTP-Server via SSHFS protocol 
import sys
import os
import subprocess
def mount():
#Function for mounting the networked drive
 if os.path.exists('/home/user/MNT/MEDIA/'):
 print('Network drive is mounted')
 un = input("To unmount type U/u \n")
 if un == "u" or un == "U":
 subprocess.call(['sudo fusermount -u /home/user/MNT/'], shell=True) 
 else:
 pass 
 exit(0) 
 if not os.path.exists('/home/user/MNT/MEDIA/'):
 IP = input("Type I/i for local connection, E/e for external\n")
 if IP == "i" or IP == "I":
 subprocess.call(['sudo sshfs -o idmap=user -o uid=1000 -o gid=1000 -o allow_other -o default_permissions -p 100 [email protected]:/media/Hitachi/ /home/user/MNT'], shell=True)
 if IP == "e" or IP == "E":
 subprocess.call(['sudo sshfs -o idmap=user -o uid=1000 -o gid=1000 -o allow_other -o default_permissions -p 100 [email protected]/media/Hitachi/ /home/user/MNT'], shell=True) 
 elif IP == "": #returns if null value 
 return mount()
def makedir():
#Function to check and see if directory is created and if not create it
 if not os.path.exists('/home/user/MNT/'):
 subprocess.call(['sudo mkdir /home/user/MNT/'], shell=True)
 if os.path.isdir('/home/user/MNT/'):
 mount() 
makedir()

EDITED:

def sshfs():
#function to mount network drive
 while True:
 user = input("Type 'i' for internal, 'e' for external connection\n")
 fs = File_System.get(user.lower()) #Get value from the dict called File_System
 if fs is None:
 print("Invalid option, enter either 'i' for internal or 'e' for external\n")
 else:
 subprocess.call(["sudo sshfs -o uid=1000 -o gid=1000 -o idmap=user -o default_permissions -o allow_other -p 100 %s %s" % (fs, Local_Mount)], shell=True)
 exit(0)

• rolfl: Please provide some more context. Looking at the code tells us one what you are actually doing, but having a general description of what you want to do may give some opportunity to provide alternative suggestions too.
• Joseph: Just trying to make a script to use with all my linux machines to mount to a centralized server

Answer 1

Efficiency is just not an issue in this kind of task. As "glue" code, it's not computationally intensive. There are, however, some maintainability issues.

• In mount(), the basic outline is:

  def mount():
   if os.path.exists('/home/user/MNT/MEDIA/'):
   ...
   exit(0) 
   if not os.path.exists('/home/user/MNT/MEDIA/'):
   ...
  

  ... which should be expressed as:

  def mount_or_unmount():
   if os.path.exists('/home/user/MNT/MEDIA/'):
   ...
   else:
   ...
  

• Using recursion for error handling is weird. That would normally be handled using a while-loop. It's also slightly odd that the empty string triggers a retry, but any other invalid input would exit the script.

• The two sudo sshfs commands differ only slightly. Your code should be structured accordingly.

  REMOTE_FS = {
   'i': '[email protected]:/media/Hitachi/',
   'e': '[email protected]/media/Hitachi/',
  }
  ...
  while True:
   ip = input("Type I/i for local connection, E/e for external\n")
   fs = REMOTE_FS.get(ip.lower())
   if fs is None: # Input was not 'i' or 'e'
   continue
   subprocess.call(['sudo sshfs -o idmap=user -o uid=1000 -o gid=1000 -o allow_other -o default_permissions -p 100 %s /home/user/MNT' % (fs)], shell=True)
   break
  

• Joseph: Awesome, I reedited my code and I learned a lot, especially with reducing 'glue' code. However I have one question and I need it dumbed down while True: Till what is true? Why/How does the loop end?
• 200_success: Yikes! Forgot a very important break. Good catch!
• Joseph: I did it slightly different. I'm still confused as to why the loop breaks even without the break statement?:
• Erbureth: @Joe exit(0) in your case is the equivalent of break