Strategy.py

# Strategy Pattern for GIS Data Processing
# As derived from:
# https://refactoring.guru/design-patterns/strategy/python/example#lang-features

from abc import ABC, abstractmethod


class Strategy(ABC):
    # Using ABC (Abstract-Base-Class) and @abstractmethod forces
    #  the user to redefine the "main" method
    @abstractmethod
    def main(self):
        pass


class KMLProcessor(Strategy):
    def main(self, data):
        # KML Processing code goes here
        return  # Return the result


class GPXProcessor(Strategy):
    def main(self, data):
        # GPX Processing code goes here
        return  # Return the result


class GeneralizedProcessor(object):
    def __init__(self):
        # Set the default strategy to None
        self._strategy = None

    @property
    def strategy(self) -> Strategy:
        # This is required for the following
        return self._strategy

    @strategy.setter
    def strategy(self, strategy: Strategy) -> None:
        # This enforces that the type is a subclass of Strategy
        self._strategy = strategy

    def process_data(self, geo_data):
        """General processing method."""
        # This will change the "strategy" based on type, so it can handle .kml and/or .gpx files
        if geo_data.endswith(".kml"):
            self._strategy = KMLProcessor()
        elif geo_data.endswith(".gpx"):
            self._strategy = GPXProcessor()

        result = self._strategy.main(geo_data)
        return result


if __name__ == "__main__":
    # Initialize the processor (for everything)
    processor = GeneralizedProcessor()
    processor.process_data(r"C:\pat\to\myData\data.kml")
    processor.process_data(r"C:\pat\to\myData\data.gpx")