python-dependency-injector/examples/providers/provided_instance.py

"""Example of the injecting of provided instance attributes and items."""

from dependency_injector import containers, providers


class Service:
    def __init__(self):
        self.value = 'foo'
        self.values = [self.value]

    def get_value(self):
        return self.value

    def __getitem__(self, item):
        return self.values[item]


class Client:
    def __init__(self, value1, value2, value3, value4):
        self.value1 = value1
        self.value2 = value2
        self.value3 = value3
        self.value4 = value4


class Container(containers.DeclarativeContainer):

    service = providers.Singleton(Service)

    client_factory = providers.Factory(
        Client,
        value1=service.provided[0],
        value2=service.provided.value,
        value3=service.provided.values[0],
        value4=service.provided.get_value.call(),
    )


if __name__ == '__main__':
    container = Container()

    client = container.client_factory()
    assert client.value1 == client.value2 == client.value3 == 'foo'