fix(event_handler): Allow for event_source support

Changes:
- Allow for event being of type 'BaseProxyEvent'
- Add test case

closes #1152

Author: Michael Brewer

Diff for: aws_lambda_powertools/event_handler/api_gateway.py

@@ -491,6 +491,8 @@ def resolve(self, event, context) -> Dict[str, Any]:
         dict
             Returns the dict response
         """
+        if isinstance(event, BaseProxyEvent):
+            event = event.raw_event
         if self._debug:
             print(self._json_dump(event), end="")
         BaseRouter.current_event = self._to_proxy_event(event)

Diff for: tests/functional/event_handler/test_api_gateway.py

@@ -31,7 +31,12 @@
 )
 from aws_lambda_powertools.shared import constants
 from aws_lambda_powertools.shared.json_encoder import Encoder
-from aws_lambda_powertools.utilities.data_classes import ALBEvent, APIGatewayProxyEvent, APIGatewayProxyEventV2
+from aws_lambda_powertools.utilities.data_classes import (
+    ALBEvent,
+    APIGatewayProxyEvent,
+    APIGatewayProxyEventV2,
+    event_source,
+)
 from tests.functional.utils import load_event
 
 
@@ -1210,3 +1215,23 @@ def handle_not_found(_) -> Response:
 
     # THEN call the @app.not_found() function
     assert result["statusCode"] == 404
+
+
+def test_event_source_compatibility():
+    # GIVEN
+    app = APIGatewayHttpResolver()
+
+    @app.post("/my/path")
+    def my_path():
+        assert isinstance(app.current_event, APIGatewayProxyEventV2)
+        return {}
+
+    # WHEN
+    @event_source(data_class=APIGatewayProxyEventV2)
+    def handler(event: APIGatewayProxyEventV2, context):
+        assert isinstance(event, APIGatewayProxyEventV2)
+        return app.resolve(event, context)
+
+    # THEN
+    result = handler(load_event("apiGatewayProxyV2Event.json"), None)
+    assert result["statusCode"] == 200