fix(event_handler): allow responses and metadata when using Router (#3514)

Co-authored-by: Heitor Lessa <lessa@amazon.com>

Author: rubenfonseca

aws_lambda_powertools/event_handler/api_gateway.py

@@ -40,6 +40,7 @@
     validation_error_definition,
     validation_error_response_definition,
 )
+from aws_lambda_powertools.event_handler.util import _FrozenDict
 from aws_lambda_powertools.shared.cookies import Cookie
 from aws_lambda_powertools.shared.functions import powertools_dev_is_set
 from aws_lambda_powertools.shared.json_encoder import Encoder
@@ -2130,8 +2131,10 @@ def route(
         middlewares: Optional[List[Callable[..., Any]]] = None,
     ):
         def register_route(func: Callable):
-            # Convert methods to tuple. It needs to be hashable as its part of the self._routes dict key
+            # All dict keys needs to be hashable. So we'll need to do some conversions:
             methods = (method,) if isinstance(method, str) else tuple(method)
+            frozen_responses = _FrozenDict(responses) if responses else None
+            frozen_tags = frozenset(tags) if tags else None
 
             route_key = (
                 rule,
@@ -2141,9 +2144,9 @@ def register_route(func: Callable):
                 cache_control,
                 summary,
                 description,
-                responses,
+                frozen_responses,
                 response_description,
-                tags,
+                frozen_tags,
                 operation_id,
                 include_in_schema,
             )

aws_lambda_powertools/event_handler/util.py

@@ -0,0 +1,13 @@
+class _FrozenDict(dict):
+    """
+    A dictionary that can be used as a key in another dictionary.
+
+    This is needed because the default dict implementation is not hashable.
+    The only usage for this right now is to store dicts as part of the Router key.
+    The implementation only takes into consideration the keys of the dictionary.
+
+    MAINTENANCE: this is a temporary solution until we refactor the route key into a class.
+    """
+
+    def __hash__(self):
+        return hash(frozenset(self.keys()))

tests/functional/event_handler/test_openapi_params.py

@@ -4,7 +4,7 @@
 
 from pydantic import BaseModel
 
-from aws_lambda_powertools.event_handler.api_gateway import APIGatewayRestResolver, Response
+from aws_lambda_powertools.event_handler.api_gateway import APIGatewayRestResolver, Response, Router
 from aws_lambda_powertools.event_handler.openapi.models import (
     Example,
     Parameter,
@@ -392,6 +392,38 @@ def secret():
     assert len(schema.paths.keys()) == 0
 
 
+def test_openapi_with_router_response():
+    router = Router()
+
+    @router.put("/example-resource", responses={200: {"description": "Custom response"}})
+    def handler():
+        pass
+
+    app = APIGatewayRestResolver(enable_validation=True)
+    app.include_router(router)
+
+    schema = app.get_openapi_schema()
+    put = schema.paths["/example-resource"].put
+    assert 200 in put.responses.keys()
+    assert put.responses[200].description == "Custom response"
+
+
+def test_openapi_with_router_tags():
+    router = Router()
+
+    @router.put("/example-resource", tags=["Example"])
+    def handler():
+        pass
+
+    app = APIGatewayRestResolver(enable_validation=True)
+    app.include_router(router)
+
+    schema = app.get_openapi_schema()
+    tags = schema.paths["/example-resource"].put.tags
+    assert len(tags) == 1
+    assert tags[0].name == "Example"
+
+
 def test_create_header():
     header = _Header(convert_underscores=True)
     assert header.convert_underscores is True