config-manager-evjeny 0.2.0

Small config manager for parsing configs from different sources

config_manager

Configuration manager for parsing from different sources

Installation

python -m pip install config-manager-evjeny

Usage

Create class with config variables and inherit it from config_manager.config.Config. You can define variables and their types or even define values. Then we can parse variables from different sources. For example, this is example_parser.py:

from config_manager import config


class TestConfig(config.Config):
    name: str
    age: int
    is_useful: bool = False


my_config = TestConfig()
config.parse_env(my_config, prefix="test_config_")
config.parse_json(my_config, json_path="test_config.json")
config.parse_arguments(my_config, "TestConfig parser")

print(my_config)

If we run it:

test_config_age=33 python example_parser.py \
  --name hello \
  --is_useful false \
  --parts 0.25 0.5 0.75

It will output something like and all the primitive types will be parsed correctly:

age = 33
is_useful = False
name = hello
parts = [0.25, 0.5, 0.75]

Type details

str, int and float

For str, int and float casting is the same as builtin functions.

BoolType

Generally all not empty containers (even string "false") cast to bool would return True.

Thus, there is custom type BoolType. Variable cast to BoolType will get True value in one of these cases:

• variable is subclass of str and it's value one of (in any case):
  • "yes"
  • "true"
  • "1"
  • "on"
• variable is numeric, and it's value is 1 (or 1.0)

from config_manager.config_types import BoolType

assert BoolType("yes") == True
assert BoolType("yES") == True
assert BoolType("tRuE") == True
assert BoolType("1") == True
assert BoolType("on") == True

assert BoolType("no") == False
assert BoolType("FaLsE") == False

assert BoolType(1.0) == True
assert BoolType(0.0) == False
assert BoolType(1) == True
assert BoolType(0) == False
assert BoolType(True) == True
assert BoolType(False) == False

ListType

As it is impossible to get type from typing.List[T] (plus this annotation removed in Python 3.9) there is a ListType. It can be used with any of primitives, so every element will be cast to primitive's type. For example:

from config_manager.config_types import ListType

assert ListType[int](["1", "2", "3"]) == [1, 2, 3]
assert ListType[str]([1.0, -213.5122, 52.123]) == ["1.0", "-213.5122", "52.123"]

All the parse sources provide different ways to define list, so there they are:

• in predefine and json case simply assign any python list to variable
• in environment case provide list separated by comma without spaces, like my_cool_list=hello,world,ough
• in argument case put list items separated by spaces after variable name, like --cool_list 1 2 3 1123