Source code for pldl.skeleton

"""
This is a skeleton file that can serve as a starting point for a Python
console script. To run this script uncomment the following lines in the
``[options.entry_points]`` section in ``setup.cfg``::

    console_scripts =
         fibonacci = pldl.skeleton:run

Then run ``pip install .`` (or ``pip install -e .`` for editable mode)
which will install the command ``fibonacci`` inside your current environment.

Besides console scripts, the header (i.e. until ``_logger``...) of this file can
also be used as template for Python modules.

Note:
    This file can be renamed depending on your needs or safely removed if not needed.

References:
    - https://setuptools.pypa.io/en/latest/userguide/entry_point.html
    - https://pip.pypa.io/en/stable/reference/pip_install
"""

import argparse
import logging
import sys

from pldl import __version__

__author__ = "Wai-Shing Luk"
__copyright__ = "Wai-Shing Luk"
__license__ = "MIT"

_logger = logging.getLogger(__name__)


# ---- Python API ----
# The functions defined in this section can be imported by users in their
# Python scripts/interactive interpreter, e.g. via
# `from pldl.skeleton import fib`,
# when using this Python module as a library.


[docs]def fib(n): """Fibonacci example function Args: n (int): integer Returns: int: n-th Fibonacci number """ assert n > 0 a, b = 1, 1 for _i in range(n - 1): a, b = b, a + b return a
# ---- CLI ---- # The functions defined in this section are wrappers around the main Python # API allowing them to be called directly from the terminal as a CLI # executable/script.
[docs]def parse_args(args): """Parse command line parameters Args: args (List[str]): command line parameters as list of strings (for example ``["--help"]``). Returns: :obj:`argparse.Namespace`: command line parameters namespace """ parser = argparse.ArgumentParser(description="Just a Fibonacci demonstration") parser.add_argument( "--version", action="version", version=f"pldl {__version__}", ) parser.add_argument(dest="n", help="n-th Fibonacci number", type=int, metavar="INT") parser.add_argument( "-v", "--verbose", dest="loglevel", help="set loglevel to INFO", action="store_const", const=logging.INFO, ) parser.add_argument( "-vv", "--very-verbose", dest="loglevel", help="set loglevel to DEBUG", action="store_const", const=logging.DEBUG, ) return parser.parse_args(args)
[docs]def setup_logging(loglevel): """Setup basic logging Args: loglevel (int): minimum loglevel for emitting messages """ logformat = "[%(asctime)s] %(levelname)s:%(name)s:%(message)s" logging.basicConfig( level=loglevel, stream=sys.stdout, format=logformat, datefmt="%Y-%m-%d %H:%M:%S" )
[docs]def main(args): """Wrapper allowing :func:`fib` to be called with string arguments in a CLI fashion Instead of returning the value from :func:`fib`, it prints the result to the ``stdout`` in a nicely formatted message. Args: args (List[str]): command line parameters as list of strings (for example ``["--verbose", "42"]``). """ args = parse_args(args) setup_logging(args.loglevel) _logger.debug("Starting crazy calculations...") print(f"The {args.n}-th Fibonacci number is {fib(args.n)}") _logger.info("Script ends here")
[docs]def run(): """Calls :func:`main` passing the CLI arguments extracted from :obj:`sys.argv` This function can be used as entry point to create console scripts with setuptools. """ main(sys.argv[1:])
if __name__ == "__main__": # ^ This is a guard statement that will prevent the following code from # being executed in the case someone imports this file instead of # executing it as a script. # https://docs.python.org/3/library/__main__.html # After installing your project with pip, users can also run your Python # modules as scripts via the ``-m`` flag, as defined in PEP 338:: # # python -m pldl.skeleton 42 # run()