Key steps to build a CLI

Creating a command-line interface (CLI) for a Python program has become easier to me when I see it as these keys steps ^[1] :

1. Initialize

2. Configure

3. Parse

4. Use

For example, using argparse:

1. Initialize

   import argparse
   

2. Configure

   parser = argparse.ArgumentParser()
   parser.add_argument(...)
   ...
   

3. Parse

   args = parser.parse_args()
   

4. Use

   if args.attribute:
     # do something
   

When the configure step has many commands, I use a function:

def config_parser():
    parser = argparse.ArgumentParser()
    parser.add_argument(...)
    ...
    return parser

and step 2. becomes:

parser = config_parser()

References

1. I was inspired by the Matplotlib for beginners handout. It is part of a series