Figenv

Metaclass for handling configuration class objects using environment variables.

If an environment variable is specified, the metaclass will pull the variable from the environment, the variable defined on the class will be used.

This was built to be a dropin replacement for flask-env but supporting change environment variables after the meta class is loaded.

Config

There are 2 configuration options, that are set on the base class object.

ENV_LOAD_ALL = <True/False>

Setting this on the class will allow loading any environment variable even if it is not set on the base class.

ENV_PREFIX = <string>

Setting this will will be a prefix for variables in the environment.

Install

This should just be pip installed

python3 -m pip install figenv

Usage

The basic usecase is below.

 import os

 import figenv

 class Config(metaclass=figenv.MetaConfig):

     ENV_LOAD_ALL = True
     ENV_PREFIX = 'ROCKSTEADY_'

     BLAH = True
     TIMEOUT = 5
     POSTGRES_HOST = 'localhost'
     POSTGRES_PORT = 5432
     POSTGRES_USER = 'bebop'
     POSTGRES_PASS = 'secret'
     POSTGRES_DB = 'main'

     def SQLALCHEMY_DATABASE_URI(cls):
         return 'postgresql://{user}:{secret}@{host}:{port}/{database}?sslmode=require'.format(
             user=cls.POSTGRES_USER,
             secret=cls.POSTGRES_PASS,
             host=cls.POSTGRES_HOST,
             port=cls.POSTGRES_PORT,
             database=cls.POSTGRES_DB,
         )

assert Config.TIMEOUT == 5
assert Config.BLAH is True
assert Config.SQLALCHEMY_DATABASE_URI == 'postgresql://bebop:secret@localhost:5432/main?sslmode=require'
try:
    Config.WHAT
except AttributeError:
    pass

os.environ.update({
    'ROCKSTEADY_BLAH': 'false',
    'ROCKSTEADY_TIMEOUT': '15',
    'ROCKSTEADY_WHAT': '2.9',
    'ROCKSTEADY_SQLALCHEMY_DATABASE_URI': 'postgres://localhost:5432/db',
})

assert Config.TIMEOUT == 15
assert Config.BLAH is False
assert Config.WHAT == 2.9
assert Config.SQLALCHEMY_DATABASE_URI == 'postgres://localhost:5432/db'