mec

Mat's Easy CLI

Example

from typing import List

from subparser import cli


@cli(name='example', description='An example command.')
def example(v: bool = True):
    return {'verbose': v}

@example.command(help="Command help.", param="Param help.", flag="Activate flag.")
def test(param: str = None, flag: bool = True):
    print("Invoked command test")

    if param:
        print(f"with param: {param}")
    if flag:
        print("Flag activated.")
    if example.ctx['verbose']:
        print("Verbose")


@example.command
def test2():
    print("Invoked command test2.")


@example.command(
    help="Add both args.", a="First number to add", b="Second number to add"
)
def add(a: int, b: int):
    print(a + b)


@example.command
def nargs(a: List[str]):
    print(f"Got {len(a)} args: {a}")


if __name__ == "__main__":
    example.main()

• Top level help:

$ ./venv/bin/python src/subparser/example.py -h
usage: example [-h] [-v] {test,test2,add} ...

An example command.

positional arguments:
  {test,test2,add}
    test            Command help.
    test2
    add             Add both args.

optional arguments:
  -h, --help        show this help message and exit
  -v

• Invoking command with args:

$ ./venv/bin/python src/subparser/example.py test
Invoked command test
$ ./venv/bin/python src/subparser/example.py test --flag
Invoked command test
Flag activated.
$ ./venv/bin/python src/subparser/example.py test --flag --param one
Invoked command test
with param: one
Flag activated.
$ ./venv/bin/python src/subparser/example.py -v test --flag --param one
Invoked command test
with param: one
Flag activated.
Verbose

• Invoking command with positionnal args:

$ ./venv/bin/python src/subparser/example.py add 31 11
42
$ ./venv/bin/python src/subparser/example.py add a b
usage: example add [-h] a b
example add: error: argument a: invalid int value: 'a'

• Invoking a command with append style args:

$ ./venv/bin/python src/subparser/example.py nargs a b c
Got 3 args: ['a', 'b', 'c']
$ ./venv/bin/python src/subparser/example.py nargs 42
Got 1 args: ['42']

• Subcommand help:

$ ./venv/bin/python src/subparser/example.py add -h
usage: example add [-h] a b

positional arguments:
  a           First number to add
  b           Second number to add

optional arguments:
  -h, --help  show this help message and exit