Cliche

Build a simple command-line interface from your functions.

Features:

• ✓ Least syntax required: you do not need to "learn a library" to use this
• ✓ keeps it DRY (Don't Repeat yourself):
  • it uses all information available like annotations, default values and docstrings... yet does not require them.
• ✓ Just decorate a function with @cli - that is it - it can now be called as CLI but also remains usable by other functions (unlike the click library)
• ✓ Works with booleans (flags) and lists (multiple args) automatically
• ✓ Standing on the shoulders of giants (i.e. it uses argparse and learnings from others)
• ✓ Prints returned python objects in JSON (unless passing --raw)
• ✓ Colorized output automatically
• ✓ Allows creating executable by using cliche install <mycli>
• ✓ Creates shortcuts, e.g. a variable "long_option" will be usable like --long-option and -l
• ✓ No external dependencies -> lightweight

Examples

Simplest Example

You want to make a calculator. You not only want its functions to be reusable, you also want it to be callable from command line.

# calculator.py
from cliche import cli

@cli
def add(a: int, b: int):
    return a + b

Now let's see how to use it from the command-line:

pascal@archbook:~/calc$ cliche install calc
pascal@archbook:~/calc$ calc add --help

usage: calc add [-h] a b

positional arguments:
  a           |int|
  b           |int|

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

thus:

pascal@archbook:~/calc$ calc add 1 10
11

Installation of commands

You noticed we ran

cliche install calc

We can undo this with

cliche uninstall calc

Note that installing means that all @cli functions will be detected in the folder, not just of a single file, even after installation. You only have to install once, and on Linux it also adds autocompletion to your CLI if argcomplete has been installed.

Advanced Example

from cliche import cli

@cli
def add_or_mul(a_number: int, b_number=10, sums=False):
    """ Adds or multiplies a and b

    :param a_number: the first one
    :param b_number: second one
    :param sums: Sums when true, otherwise multiply
    """
    if sums:
        print(a_number + b_number)
    else:
        print(a_number * b_number)

Help:

Calling it:

pascal@archbook:~/calc$ calc add_or_mul 1
10

pascal@archbook:~/calc$ calc add_or_mul --sum 1
11

pascal@archbook:~/calc$ calc add_or_mul 2 -b 3
6

More examples

Check the example files here

Comparison with other CLI generators

• argparse: it is powerful, but you need a lot of code to construct an argparse CLI
• click: you need a lot of decorators to construct a CLI, and not obvious how to use it. It does not keep things DRY. Also, the annotated function is not usable.
• hug (cli): connected to a whole web framework, but gets a lot right
• python-fire: low set up, but annoying traces all the time / ugly design, does not show default values nor types
• cleo: requires too much code/objects to construct