typenv

Version 0.1.2

Typed environment variable parsing for Python

Background

Typenv does environment variable parsing with an API almost identical to the excellent environs. There are a few reasons why typenv might be preferred:

• Type annotated typecast functions: type checkers are able to understand types of parsed environment variables.
• More flexible prefix manipulation of environment variable names.
• Validation of environment variable names.
• Optional automatic uppercasing of environment variable names.
• Ability to generate a .env.example that shows expected types of environment variables.
• Less dependencies. No marshmallow required.

Installing

Installing from PyPI repository (https://pypi.org/project/typenv):

pip install typenv

Usage

Basics

Set environment variables:

export NAME='Harry Potter'
export AGE=14
export IS_WIZARD=true
export PATRONUM_SUCCESS_RATE=0.92
export BANK_BALANCE=134599.01
export LUCKY_NUMBERS=7,3,11
export EXTRA_DETAILS='{"friends": ["Hermione", "Ron"]}'

Parse the values in Python:

from typenv import Env

env = Env()

NAME = env.str("NAME")  # => "Harry Potter"
AGE = env.int("AGE")  # => 14
IS_WIZARD = env.bool("IS_WIZARD")  # => True
PATRONUM_SUCCESS_RATE = env.float("PATRONUM_SUCCESS_RATE")  # => 0.92
BANK_BALANCE = env.decimal("BANK_BALANCE")  # => decimal.Decimal("134599.01")
LUCKY_NUMBERS = env.list("LUCKY_NUMBERS", subcast=int)  # => [7, 3, 11]
EXTRA_DETAILS = env.json("EXTRA_DETAILS")  # => {"friends": ["Hermione", "Ron"]}

# Optional settings must have a default value
IS_DEATH_EATER = env.bool("IS_DEATH_EATER", default=False)  # => False

Supported types

The types supported by typenv are:

• env.str
• env.int
• env.bool
• env.float
• env.decimal
• env.json
• env.list
  • Takes a subcast argument for casting list items to one of str, int , bool, float or decimal.Decimal

Default values

TODO:

Name prefixes

TODO:

Name uppercasing

TODO:

Validation

TODO:

Reading from a .env file

TODO:

Dumping parsed values

TODO:

Acknowledgments

The public API of this library is almost an exact copy of environs, which is based on envparse and django-environ. Credit for the interface goes to the authors of those libraries.