Services

Use service objects to implement functionality in your application. Services can depend on configuration or other services.

Registration

Wireup does not enforce a code structure. Services may live anywhere, but must be registered with the container.

To register a class as a service you can decorate it with @service or @abstract. In addition, the modules where services reside must be passed to the service_modules parameter in the wireup.create_container call.

Good to know

Note that you don't need to register each module separately, only the top level modules are sufficient as the container will perform a recursive scan.

Lifetime

By default, the container will keep in memory only a single copy of each service. If you need to generate fresh instances every time a service is injected, then it needs to be registered with the lifetime parameter set to TRANSIENT.

Injection

To request a service in another serivce simply set the type in the init method. The name of the argument does not matter, only the type is used to detect dependencies.

@service
class FooService:
    def __init__(self, bar: BarService) -> None: ...

Most of the time no additional configuration is needed.

Tip

Refer to the documentation regarding Annotations for the exact details on when you need to explicitly annotate your dependencies.