HeartSaVioR commented on code in PR #47933: URL: https://github.com/apache/spark/pull/47933#discussion_r1746512565
########## python/pyspark/sql/streaming/stateful_processor.py: ########## @@ -77,6 +78,58 @@ def clear(self) -> None: self._value_state_client.clear(self._state_name) +class ListState: + """ + Class used for arbitrary stateful operations with transformWithState to capture single value + state. + + .. versionadded:: 4.0.0 + """ + + def __init__( + self, list_state_client: ListStateClient, state_name: str, schema: Union[StructType, str] + ) -> None: + self._list_state_client = list_state_client + self._state_name = state_name + self.schema = schema + + def exists(self) -> bool: + """ + Whether list state exists or not. + """ + return self._list_state_client.exists(self._state_name) + + def get(self) -> Iterator["PandasDataFrameLike"]: Review Comment: We consider Spark SQL's Row as the base type of the state. ValueState followed the underlying implementation, and I expect all types to follow the same. I'm OK to accept PandasDataFrameLike, but it should be secondary type of support (should be `Union[Row, PandasDataFrameLike]`) and we need to take care of conversion to finally store them to "Row". (We need to error out when given pandas DataFrame does not fit with the state schema.) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org