environment pattern

environment.py

import os


class EnvironmentConfiguration():
    def __init__(cls):
        cls.name = os.environ.get('ENV_NAME', 'development')
        cls.required_variable = os.environ.get('REQUIRED_VARIABLE')
        cls.some_integer = int(os.environ.get('COOLNESS_LEVEL'))
        cls.some_array = str(os.environ.get('GREAT_IDEAS')).split(',')

        if not cls.required_variable:
            raise Exception('REQUIRED_VARIABLE is not set in the environment variables.')


ENV = EnvironmentConfiguration()

other_file.py

from .environment import ENV

# my editor has cool type hints and autocomplete with this useful typed object
if ENV.name == 'something':
  print('incredible')

other_file_yolo.py

# don't do this
import os


# no editor autocomplete, I'm clicking back and forth, copying strings all over the place, bound to cause a typo
if os.environ.get('REQUIRED_VARIABLE') == '1':
  print('great')
  
if os.environ.get('COOLNESS_LEVEL'):
  # check the types
  value = os.environ.get('COOLNESS_LEVEL')
  if isinstance(value, str):
    value = value.split(',')
  # now we can finally use the value