iocpy3 0.1.1

Simple ioc framework for python

Simple Python IoC Framework

Usage

Examples how to use this library.

Singleton with no dependency's

Registering a singleton means we will return the same instance for every ioc.get request.

class MyInterface(ABC):
    @abstractmethod
    def do_it(self):
        ...

class MyClass(MyInterface):

    def __init__(self, name):
        self.name = name

    def do_it(self):
        print(f"{self.name} I did it")

ioc = IOCContainer()
ioc.register_singleton(MyInterface, MyClass("John Doe"))
ioc.get(MyInterface).do_it()

Singleton with dependency's

Creating a singleton with dependency enables us to reuse already registered configurations.

⚠️ A singleton should only have singletons as dependency's if we use a transient, the transient will become a singleton.

class AppConfig(BaseModel):
    user_name: str

ioc = IOCContainer()
ioc.register_singleton(AppConfig, AppConfig(user_name="John Doe"))
ioc.register_singleton(MyInterface, lambda x: MyClass(
    name=x.get(AppConfig).user_name)
    )
ioc.get(MyInterface).do_it()

Transient

Registering a transient means we will generate the instance for every ioc.get request.

class LoveCalculator():
    def __init__(self, name: str):
        self.name = name
        self.in_love_percent = random.randint(0, 100)

    def print(self):
        print(f"[{self.name}] -> {self.in_love_percent}%")

ioc = IOCContainer()
ioc.register_singleton(AppConfig, AppConfig(user_name="John Doe"))
ioc.register_transient(LoveCalculator, lambda x: LoveCalculator(
    name=x.get(AppConfig).username)
    )

ioc.get(LoveCalculator).print()
# output: John Doe -> 20%

ioc.get(LoveCalculator).print()
# output: John Doe -> 53%

Scoped

Register a scoped resource this can be used to get the same instance every time as long as you are in the scope. Another usage could be session aware stuff like opening and closing a db session within that scope.

class Database():
    def __init__(self, connection_string: str):
        self._cs = connection_string
        self._session_factory = SessionFactory()

    def get_session(self) -> Generator[Session, None, None]
        session = self._session_factory()
        try:
            yield session
        except:
            session.rollback()
        finally:
            session.close()


ioc = IOCContainer()
ioc.register_singleton(AppConfig, AppConfig(connection_string="Secret123"))
ioc.register_singleton(Database, lambda x: Database(
    connection_string=x.get(AppConfig).connection_string
    )
)
ioc.register_scoped(Session, lambda: x.get(Database).get_session)
ioc.register_transient(LoveCalculator, lambda x: LoveCalculator(
    db_session = x.get(Session)
))

#DB Session gets automatically closed when leaving the scope 
with ioc.create_scope() as scope:
    scope.get(LoveCalculator).print()

Development

Run basic tests

pdm test

Run coverage check

pdm coverage

Build and deploy

pdm build
pdm publish