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

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

from dependency_injector import 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


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