"""Example of several Dependency Injector IoC containers. Alternative injections definition style #1. """ import sqlite3 import boto.s3.connection import example.main import example.services import dependency_injector.containers as containers import dependency_injector.providers as providers class Platform(containers.DeclarativeContainer): """IoC container of platform service providers.""" database = providers.Singleton(sqlite3.connect) \ .add_args(':memory:') s3 = providers.Singleton(boto.s3.connection.S3Connection) \ .add_kwargs(aws_access_key_id='KEY', aws_secret_access_key='SECRET') class Services(containers.DeclarativeContainer): """IoC container of business service providers.""" users = providers.Factory(example.services.Users) \ .add_kwargs(db=Platform.database) auth = providers.Factory(example.services.Auth) \ .add_kwargs(db=Platform.database, token_ttl=3600) photos = providers.Factory(example.services.Photos) \ .add_kwargs(db=Platform.database, s3=Platform.s3) class Application(containers.DeclarativeContainer): """IoC container of application component providers.""" main = providers.Callable(example.main.main) \ .add_kwargs(users_service=Services.users, auth_service=Services.auth, photos_service=Services.photos)