batconf 0.1.8

Application configuration tool from the BAT project

BatConf

Configuration Management for Python projects, modules, applications, and microservices.

Compose structured hierarchical configurations from multiple sources. Enable your code to adapt seemlessly to the current context. Allow users in different contexts to use the config source that works best for them.

• Hierarchical priority: CLI > Environment > config file > module defaults
• Provides builtin support for common config sources:
  • CLI args
  • Environment Variables
  • Config File (yaml)
  • Config classes with default values
• Easily extendable, add new sources to serve your needs.
• Set reasonable defaults, and override them as needed.
• Designed for 12-factor applications (config via Environment Variables)

Users can create their own config sources by creating classes that satisfy batconf.source.SourceInterfaceProto (or subclass batconf.source.SourceInterface)

The config lookup order is determined by the SourceList instance, which can be adjusted to suit your needs.

Example Configuration

• REF: template project example
• tests/example/ contains an example project and tests with documentation.

Most projects can copy this example with minimal modification.

from bat import GlobalConfig

from batconf.manager import Configuration, ConfigProtocol

from batconf.source import SourceList
from batconf.sources.args import CliArgsConfig, Namespace
from batconf.sources.env import EnvConfig
from batconf.sources.file import FileConfig
from batconf.sources.dataclass import DataclassConfig


def get_config(
    # Known issue: https://github.com/python/mypy/issues/4536
    config_class: ConfigProtocol = GlobalConfig,  # type: ignore
    cli_args: Namespace = None,
    config_file: FileConfig = None,
    config_file_name: str = None,
    config_env: str = None,
) -> Configuration:

    # Build a prioritized config source list
    config_sources = [
        CliArgsConfig(cli_args) if cli_args else None,
        EnvConfig(),
        config_file if config_file else FileConfig(
            config_file_name, config_env=config_env
        ),
        DataclassConfig(config_class),
    ]

    source_list = SourceList(config_sources)

    return Configuration(source_list, config_class)

GlobalConfig and Config classes

the GlobalConfig class is a python dataclass, used for namespacing, and providing a structured configuration tree. Its attributes should be other Config dataclasses for sub-modules.

from dataclasses import dataclass
from .example import Config


@dataclass
class GlobalConfig:
    # example module with configuration dataclass
    example: Config

Install Instructions

pip install .

Install with Poetry

install poetry >= 1.1.13

poetry install

Manual install

install the dev dependencies listed in pyproject.toml

Dev Guide

Install dev dependencies (pytest, mypy, etc)

pip install -e .[dev]

macos/zsh:

pip install -e ".[dev]"

Design Principles

• Non-Intrusive Integration: BatConf can be seamlessly incorporated into existing projects with minimal code modifications.
  • imports from batconf can be isolated to a single source file
  • Config classes utilize stdlib dataclasses
• Portability and Modularity: Modules (sub-modules or entire projects) that use batconf configuration should be easy to compose and refactor.
  • modules can be easily plugged in to other modules.
  • modules can be easily factored out (into new projects).

Security contact information

To report a security vulnerability, please use the Tidelift security contact. Tidelift will coordinate the fix and disclosure.