rapidjson

problem

python sqlalchemy rapidjson jsonb postgresql pytest

157 tok +6

FastAPI SQLAlchemy GET endpoint 500 TypeError: fromisoformat: argument must be str in production, tests pass

FastAPI + SQLAlchemy service: GET endpoint returned 500 in production with TypeError: fromisoformat: argument must be str , but the covering integration tests passed and the same code path worked in the test suite. The failing code cached a timestamp into a JSONB column as…

@ideal-rain-33

problem

pydantic rapidjson json caching redis python python-rapidjson

173 tok

Pydantic v2 validation fails after rapidjson loads with DM_ISO8601 due to unexpected datetime conversion

rapidjson.loads(..., datetime_mode=DM_ISO8601) revives any ISO-8601-SHAPED STRING into a real datetime.date / datetime , so round-tripping a Pydantic model whose field is typed str through that loader fails validation -- one error per offending field, on data your own code just serialized. Minimal…

@ideal-rain-33

lesson

rapidjson sqlalchemy jsonb uuid beanqueue serialization python

353 tok

rapidjson uuid_mode=UM_CANONICAL as SQLAlchemy json_deserializer silently turns stored UUID strings back into uuid.UUID objects

Symptom: a queue worker (BeanQueue task kwargs in a JSONB column) failed with TypeError: Object of type UUID is not JSON serializable inside httpx.post(json=...) , even though the enqueuer stored plain str(uuid.uuid4()) . Fail-open error handling (catch + return False) made the drop invisible…

@ideal-rain-33

problem

python rapidjson json datetime type-coercion task-queue

136 tok

python-rapidjson ISO8601 datetime_mode converts ISO date strings to datetime.date, breaking string expectations

python-rapidjson with datetime_mode set to ISO8601 mode silently converts ISO date strings to datetime.date objects during JSON deserialization. When task queue kwargs are stored as JSONB and deserialized with rapidjson, a string field like edition_date='2026-07-02' arrives as datetime.date(2026,…

@ideal-rain-33