Merge pull request #14 from modern-python/feature/injecting-factory

implement factories injecting

packages/modern-di/modern_di/providers/factory.py

@@ -3,6 +3,7 @@
 
 from modern_di import Container
 from modern_di.providers.abstract import AbstractCreatorProvider
+from modern_di.providers.injected_factory import InjectedFactory
 
 
 T_co = typing.TypeVar("T_co", covariant=True)
@@ -21,6 +22,10 @@ def __init__(
     ) -> None:
         super().__init__(scope, creator, *args, **kwargs)
 
+    @property
+    def factory_provider(self) -> InjectedFactory[T_co]:
+        return InjectedFactory(self)
+
     async def async_resolve(self, container: Container) -> T_co:
         container = container.find_container(self.scope)
         if (override := container.fetch_override(self.provider_id)) is not None:

packages/modern-di/modern_di/providers/injected_factory.py

@@ -0,0 +1,24 @@
+import functools
+import typing
+
+from modern_di import Container
+from modern_di.providers.abstract import AbstractProvider
+
+
+T_co = typing.TypeVar("T_co", covariant=True)
+P = typing.ParamSpec("P")
+
+
+class InjectedFactory(typing.Generic[T_co]):
+    __slots__ = ("_factory_provider",)
+
+    def __init__(self, factory_provider: AbstractProvider[T_co]) -> None:
+        self._factory_provider = factory_provider
+
+    async def async_resolve(self, container: Container) -> typing.Callable[[], T_co]:
+        await self._factory_provider.async_resolve(container)
+        return functools.partial(self._factory_provider.sync_resolve, container)
+
+    def sync_resolve(self, container: Container) -> typing.Callable[[], T_co]:
+        self._factory_provider.sync_resolve(container)
+        return functools.partial(self._factory_provider.sync_resolve, container)

packages/modern-di/tests_core/providers/test_injected_factory.py

@@ -0,0 +1,54 @@
+import dataclasses
+import datetime
+
+import pytest
+from modern_di import Container, Scope, providers
+
+from tests_core.creators import create_async_resource, create_sync_resource
+
+
+@dataclasses.dataclass(kw_only=True, slots=True)
+class DependentCreator:
+    dep1: datetime.datetime
+
+
+async_resource = providers.Resource(Scope.APP, create_async_resource)
+sync_resource = providers.Resource(Scope.APP, create_sync_resource)
+request_sync_factory = providers.Factory(Scope.REQUEST, DependentCreator, dep1=sync_resource.cast)
+request_async_factory = providers.Factory(Scope.REQUEST, DependentCreator, dep1=async_resource.cast)
+
+
+async def test_injected_async_factory() -> None:
+    async with (
+        Container(scope=Scope.APP) as app_container,
+        app_container.build_child_container(scope=Scope.REQUEST) as request_container,
+    ):
+        factory = await request_async_factory.factory_provider.async_resolve(request_container)
+        instance1, instance2 = factory(), factory()
+        assert instance1 is not instance2
+        assert isinstance(instance1, DependentCreator)
+        assert isinstance(instance2, DependentCreator)
+
+
+async def test_injected_sync_factory() -> None:
+    with (
+        Container(scope=Scope.APP) as app_container,
+        app_container.build_child_container(scope=Scope.REQUEST) as request_container,
+    ):
+        factory = request_sync_factory.factory_provider.sync_resolve(request_container)
+        instance1, instance2 = factory(), factory()
+        assert instance1 is not instance2
+        assert isinstance(instance1, DependentCreator)
+        assert isinstance(instance2, DependentCreator)
+
+
+async def test_injected_async_factory_in_sync_mode() -> None:
+    with (
+        Container(scope=Scope.APP) as app_container,
+        app_container.build_child_container(scope=Scope.REQUEST) as request_container,
+    ):
+        with pytest.raises(RuntimeError, match="Resolving async resource in sync container is not allowed"):
+            await request_async_factory.factory_provider.async_resolve(request_container)
+
+        with pytest.raises(RuntimeError, match="Async resource cannot be resolved synchronously"):
+            request_async_factory.factory_provider.sync_resolve(request_container)