feat(apigateway): access parent api resolver from router (#842)

Author: Tom McCarthy

aws_lambda_powertools/event_handler/api_gateway.py

@@ -664,6 +664,10 @@ def include_router(self, router: "Router", prefix: Optional[str] = None) -> None
         prefix : str, optional
             An optional prefix to be added to the originally defined rule
         """
+
+        # Add reference to parent ApiGatewayResolver to support use cases where people subclass it to add custom logic
+        router.api_resolver = self
+
         for route, func in router._routes.items():
             if prefix:
                 rule = route[0]
@@ -678,6 +682,7 @@ class Router(BaseRouter):
 
     def __init__(self):
         self._routes: Dict[tuple, Callable] = {}
+        self.api_resolver: Optional[BaseRouter] = None
 
     def route(
         self,

tests/functional/event_handler/test_api_gateway.py

@@ -1057,3 +1057,22 @@ def foo(account_id):
     assert post_result["headers"]["Content-Type"] == content_types.APPLICATION_JSON
     assert put_result["statusCode"] == 404
     assert put_result["headers"]["Content-Type"] == content_types.APPLICATION_JSON
+
+
+def test_api_gateway_app_router_access_to_resolver():
+    # GIVEN a Router with registered routes
+    app = ApiGatewayResolver()
+    router = Router()
+
+    @router.get("/my/path")
+    def foo():
+        # WHEN accessing the api resolver instance via the router
+        # THEN it is accessible and equal to the instantiated api resolver
+        assert app == router.api_resolver
+        return {}
+
+    app.include_router(router)
+    result = app(LOAD_GW_EVENT, {})
+
+    assert result["statusCode"] == 200
+    assert result["headers"]["Content-Type"] == content_types.APPLICATION_JSON