How to run the same python script with different module import?

Question

I'm working on a project where I would like to run a same script but with two different softwares api.

What I have : -One module for each software where I have the same classes and methods names. -One construction script where I need to call these classes and method.

I would like to not duplicate the construction code, but rather run the same bit of code just by changing the imported module.

Exemple :

first_software_module.py
import first_software_api
class Box(x,y,z):
 init():
 first_software_api.makeBox()

second_software_module.py
import second_software_api
class Box(x,y,z):
 init():
 second_software_api.makeBox()

construction.py
first_box = Box(1,2,3)

And I would like to run construction.py with the first module, then with the second module. I tryed with imports, execfile, but none of these solutions seems to work.

What i would like to do :

import first_software_module
run construction.py
import second_software_module
run construction.py

• rdas: Why not pass the module name to construction & let it import it & run it?
• Gregoire: Is it possible to do that inside an other python script ? Because I have to run the construction script inside a larger script

Answer 1

You could try by passing a command line argument to construction.py.

construction.py

import sys
if len(sys.argv) != 2:
 sys.stderr.write('Usage: python3 construction.py <module>')
 exit(1)
if sys.argv[1] == 'first_software_module':
 import first_software_module
elif sys.argv[1] == 'second_software_module':
 import second_software_module
box = Box(1, 2, 3)

You could then call construction.py with each import type from a shell script, say main.sh.

main.sh

#! /bin/bash
python3 construction.py first_software_module
python3 construction.py second_software_module

Make the shell script executable using chmod +x main.sh. Run it as ./main.sh.

Alternatively, if you do not want to use a shell script, and want to do it in pure Python, you could do the following:

main.py

import subprocess
subprocess.run(['python3', 'construction.py', 'first_software_module'])
subprocess.run(['python3', 'construction.py', 'second_software_module'])

and run main.py as you normally would using python3 main.py.

• Gregoire: Actually I need to run it from inside an other python script, handling path to the software, file saves, etc... Is it possible with that solution ?
• Nikhil Kumar: I've added how you can do it in Python. Does the modification work for you?
• Gregoire: I'll give it a try

Answer 2

You can pass a command-line argument that will tell your script which module to import. There are many ways to do this, but I'm going to demonstrate with the argparse module

import argparse
parser = argparse.ArgumentParser(description='Run the construction')
parser.add_argument('--module', nargs=1, type=str, required=True, help='The module to use for the construction', choices=['module1', 'module2'])
args = parser.parse_args()

Now, args.module will contain the contents of the argument you passed. Using this string and an if-elif ladder (or the match-case syntax in 3.10+) to import the correct module, and alias it as (let's say) driver.

if args.module[0] == "module1":
 import first_software_api as driver
 print("Using first_software_api")
elif args.module[0] == "module2":
 import second_software_api as driver
 print("Using second_software_api")

Then, use driver in your Box class:

class Box(x,y,z):
 def __init__(self):
 driver.makeBox()

Say we had this in a file called construct.py. Running python3 construct.py --help gives:

usage: construct.py [-h] --module {module1,module2}
Run the construction
optional arguments:
 -h, --help show this help message and exit
 --module {module1,module2}
 The module to use for the construction

Running python3 construct.py --module module1 gives:

Using first_software_api