If you have been writing python command line scripts, chances are you will want to make your script interactive with on the command line.
For example, you will want to set values for some variables at every start of the script. So, instead of editing the script directly, python provides module to help you define the variable at the point of running the script.
There are several modules for doing this, but we will talk about the Python
argparse module.
In the script below for example, we did like to change the values of the variables "x and y" each time we want to add new set of values as seen in the script. So, each time we have to edit the script from the text editor before running it.
x = 9
y = 0
print(x + y)
It would be great if we can specify new variables directly on the command line each time we run the script without editing the script directly. This is where 'Command Line Argument' comes to play.
Lets modify the script so it uses command line interface with the Python
argparse library.
There are basically five steps involved as listed below:-
1. Import 'argparse' library
2. Create the parser object
3. Add optional, required or positional arguments to the parser
4. Execute to create dictionary collection of the values using
.parse_args() method
5. Use the values from the dictionary
#1. Import 'argparse' library
import argparse
#2. Create the parser object
parser = argparse.ArgumentParser()
#3. Add optional, required or positional arguments to the parser
parser.add_argument("-x", "--x_variable", type=int, required=True, help="X numeric value")
parser.add_argument("-y", "--y_variable", type=int, required=True, help="Y numeric value")
#4. Execute to create dictionary collection of the values using .parse_args()
args = vars(parser.parse_args())
# 5. Use the values from the dictionary
x = args['x_variable']
y = args['y_variable']
print(x + y)
