Add type to define OAS responses

demo/__main__.py

@@ -1,10 +1,10 @@
 from aiohttp import web
-
-from aiohttp_pydantic import oas
 from aiohttp.web import middleware
 
-from .view import PetItemView, PetCollectionView
+from aiohttp_pydantic import oas
+
 from .model import Model
+from .view import PetCollectionView, PetItemView
 
 
 @middleware

demo/model.py

@@ -6,6 +6,10 @@ class Pet(BaseModel):
     name: str
 
 
+class Error(BaseModel):
+    error: str
+
+
 class Model:
     """
     To keep simple this demo, we use a simple dict as database to

demo/view.py

@@ -1,28 +1,32 @@
-from aiohttp_pydantic import PydanticView
+from typing import List, Union
+
 from aiohttp import web
 
-from .model import Pet
+from aiohttp_pydantic import PydanticView
+from aiohttp_pydantic.oas.typing import r200, r201, r204, r404
+
+from .model import Error, Pet
 
 
 class PetCollectionView(PydanticView):
-    async def get(self):
+    async def get(self) -> r200[List[Pet]]:
         pets = self.request.app["model"].list_pets()
         return web.json_response([pet.dict() for pet in pets])
 
-    async def post(self, pet: Pet):
+    async def post(self, pet: Pet) -> r201[Pet]:
         self.request.app["model"].add_pet(pet)
         return web.json_response(pet.dict())
 
 
 class PetItemView(PydanticView):
-    async def get(self, id: int, /):
+    async def get(self, id: int, /) -> Union[r200[Pet], r404[Error]]:
         pet = self.request.app["model"].find_pet(id)
         return web.json_response(pet.dict())
 
-    async def put(self, id: int, /, pet: Pet):
+    async def put(self, id: int, /, pet: Pet) -> r200[Pet]:
         self.request.app["model"].update_pet(id, pet)
         return web.json_response(pet.dict())
 
-    async def delete(self, id: int, /):
+    async def delete(self, id: int, /) -> r204:
         self.request.app["model"].remove_pet(id)
-        return web.json_response(id)
+        return web.Response(status=204)