Python Dependency Injection library

aiodi is a modern Python Dependency Injection library that allows you to standardize and centralize the way objects are constructed in your application highly inspired on PHP Symfony's DependencyInjection Component.

Key Features:

• Native-based: Implements PEP 621 storing project metadata in pyproject.toml.
• Dual mode: Setting dependencies using Python and using configuration files.
• Clean: Wherever you want just use it, no more decorators and defaults everywhere.

Installation

Use the package manager pip to install aiodi.

pip install aiodi

Documentation

• Visit aiodi docs.

Usage

with Configuration Files

# sample/pyproject.toml

[tool.aiodi.variables]
name = "%env(str:APP_NAME, 'sample')%"
version = "%env(int:APP_VERSION, '1')%"
log_level = "%env(APP_LEVEL, 'INFO')%"
debug = "%env(bool:int:APP_DEBUG, '0')%"
text = "Hello World"

[tool.aiodi.services."_defaults"]
project_dir = "../../.."

[tool.aiodi.services."logging.Logger"]
class = "sample.libs.utils.get_simple_logger"
arguments = { name = "%var(name)%", level = "%var(log_level)%" }

[tool.aiodi.services."UserLogger"]
type = "sample.libs.users.infrastructure.in_memory_user_logger.InMemoryUserLogger"
arguments = { commands = "@logging.Logger" }

[tool.aiodi.services."*"]
_defaults = { autoregistration = { resource = "sample/libs/*", exclude = "sample/libs/users/{domain,infrastructure/in_memory_user_logger.py,infrastructure/*command.py}" } }

# sample/apps/settings.py

from typing import Optional
from aiodi import Container, ContainerBuilder

def container(filename: str, cwd: Optional[str] = None) -> Container:
    return ContainerBuilder(filenames=[filename], cwd=cwd).load()

# sample/apps/cli/main.py

from sample.apps.settings import container
from logging import Logger

def main() -> None:
    di = container(filename='../../pyproject.toml')

    di.get(Logger).info('Just simple call get with the type')
    di.get('UserLogger').logger().info('Just simple call get with the service name')

with Python

from abc import ABC, abstractmethod
from logging import Logger, getLogger, NOTSET, StreamHandler, Formatter
from os import getenv

from aiodi import Container
from typing import Optional, Union

_CONTAINER: Optional[Container] = None


def get_simple_logger(
        name: Optional[str] = None,
        level: Union[str, int] = NOTSET,
        fmt: str = '[%(asctime)s] - %(name)s - %(levelname)s - %(message)s',
) -> Logger:
    logger = getLogger(name)
    logger.setLevel(level)
    handler = StreamHandler()
    handler.setLevel(level)
    formatter = Formatter(fmt)
    handler.setFormatter(formatter)
    logger.addHandler(handler)
    return logger


class GreetTo(ABC):
    @abstractmethod
    def __call__(self, who: str) -> None:
        pass


class GreetToWithPrint(GreetTo):
    def __call__(self, who: str) -> None:
        print('Hello ' + who)


class GreetToWithLogger(GreetTo):
    _logger: Logger

    def __init__(self, logger: Logger) -> None:
        self._logger = logger

    def __call__(self, who: str) -> None:
        self._logger.info('Hello ' + who)


def container() -> Container:
    global _CONTAINER
    if _CONTAINER:
        return _CONTAINER
    di = Container({'env': {
        'name': getenv('APP_NAME', 'aiodi'),
        'log_level': getenv('APP_LEVEL', 'INFO'),
    }})
    di.resolve([
        (
            Logger,
            get_simple_logger,
            {
                'name': di.resolve_parameter(lambda di_: di_.get('env.name', typ=str)),
                'level': di.resolve_parameter(lambda di_: di_.get('env.log_level', typ=str)),
            },
        ),
        (GreetTo, GreetToWithLogger),  # -> (GreetTo, GreetToWithLogger, {})
        GreetToWithPrint,  # -> (GreetToWithPrint, GreetToWithPrint, {})
    ])
    di.set('who', 'World!')
    # ...
    _CONTAINER = di
    return di


def main() -> None:
    di = container()

    di.get(Logger).info('Just simple call get with the type')

    for greet_to in di.get(GreetTo, instance_of=True):
        greet_to(di.get('who'))


if __name__ == '__main__':
    main()

Requirements

• Python >= 3.10

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.

License

MIT