dluman / pennant

A high-spirited feature-flagging library for Python.

pennant

A feature flagging library that uses decorators and context management to "feature flag" certain functions or blocks of code. I feel like it's better than a bunch of conditionals, but I'm often wrong.

Installation

Find this tool on PyPI: pip install pennant

Usage

Contrary to how some folks might do it, this library takes and "opt-out" approach where setting the flag to False prevents the given function or code block from running. As long as the argument provided to the decorator or content manager evaluates to False, anything's game.

Check this out:

import pennant

@pennant.FEATURE_FLAG_FUNCTION(False)
def print_me(test: str = "Hello!") -> str:
  print(test)
  return "!"

def main():
  print("This should run none of the following.")
  print_me(test = "Yes!")
  with pennant.FEATURE_FLAG_CODE(False):
    numbers = [1,2]
    print(numbers)

if __name__ == "__main__":
  main()