fix(fastapi): inherit from SerializationFailure for Odoo 19 retrying (#53)

Odoo 19's retrying() uses isinstance checks against
PG_CONCURRENCY_EXCEPTIONS_TO_RETRY instead of pgcode-based checks.
FakeConcurrentUpdateError inherited from OperationalError (a sibling of
SerializationFailure), so isinstance returned False and the exception
was re-raised instead of retried.

Author: gonzalesedwin1123

fastapi/routers/demo_router.py

@@ -8,7 +8,7 @@
 from typing import Annotated
 
 from psycopg2 import errorcodes
-from psycopg2.errors import OperationalError
+from psycopg2.errors import SerializationFailure
 
 from odoo.api import Environment
 from odoo.exceptions import AccessError, MissingError, UserError, ValidationError
@@ -138,7 +138,7 @@ async def retrying_post(
     return JSONResponse(content={"retries": tryno, "file": file.decode("utf-8")})
 
 
-class FakeConcurrentUpdateError(OperationalError):
+class FakeConcurrentUpdateError(SerializationFailure):
     @property
     def pgcode(self):
         return errorcodes.SERIALIZATION_FAILURE

fastapi/tests/test_fastapi.py

@@ -135,7 +135,6 @@ def test_lang(self):
         self._assert_expected_lang("fr-FR,en;q=0.7,en-GB;q=0.3", b'"fr_BE"')
         self._assert_expected_lang("fr-FR;q=0.1,en;q=1.0,en-GB;q=0.8", b'"en_US"')
 
-    @unittest.skip("Odoo 19: FastAPI retrying mechanism returns 500 in test mode (#53)")
     def test_retrying(self):
         """Test that the retrying mechanism is working as expected with the
         FastAPI endpoints.
@@ -146,7 +145,6 @@ def test_retrying(self):
         self.assertEqual(response.status_code, 200)
         self.assertEqual(int(response.content), nbr_retries)
 
-    @unittest.skip("Odoo 19: FastAPI retrying mechanism returns 500 in test mode (#53)")
     def test_retrying_post(self):
         """Test that the retrying mechanism is working as expected with the
         FastAPI endpoints in case of POST request with a file.