Magical Argparse Command Helper
- Get your CLI interfaces quickly
- Turn a simple class to a CLI application or an interactive interpreter.
Given:
class Calculator:
def add(self, a, b):
"""adds two numbers and prints the result"""
return a + b
def div(self, a, b):
"""divide one number by the other"""
return a / b
You can make command line application using the decorator mach1
:
from mach import mach1
@mach1()
class Calculator:
def add(self, int: a, int: b):
"""adds two numbers and prints the result"""
print(a + b)
def div(self, int: a, int: b):
"""divide one number by the other"""
print(a / b)
calc = Calculator()
calc.run()
Now if you run the module, you will get a program that you can invoke with
the flag -h
or --help
:
$ python calc.py -h
usage: calc.py [-h] {add,div} ...
positional arguments:
{add,div} commands
add adds two numbers and prints the result
div divide one number by the other
optional arguments:
-h, --help show this help message and exit
each method is a subcommand, with type checking and it's own very help. Hench, this won't work:
$ python calc.py add foo bar
usage: calc.py add [-h] b a
calc.py add: error: argument b: invalid int value: 'foo'
And this will:
$ python calc.py add 4 9
13
To see the help of the subcommand use -h
:
$ python calc.py add -h
usage: calc.py add [-h] b a
positional arguments:
b
a
optional arguments:
-h, --help show this help message and exit
With the help of the decorator mach2
you can turn your class to CLI
application and have also an iteractive shell which invoke when no
parameters are given:
$ ./examples/calc2.py
Welcome to the calc shell. Type help or ? to list commands.
calc2 > ?
Documented commands (type help <topic>):
========================================
add div exit help
calc2 > help add
adds two numbers and prints the result
calc2 > add 2 4
6
calc2 > div 6 2
3.0
calc2 > exit
Come back soon ...
$
You can get mach from PyPI using pip:
$ pip install mach.py