Hi, I saw the DoFn#getAllowedTimestampSkew has been marked as deprecated. What if a user does want to rewind back the timestamp without violating the watermark?
Consider the case where there is a GroupByKey followed by a ParDo. The GroupByKey transform groups tuples into one-hour windows. Say, each value of the output iterable of the GroupByKey remembers the timestamp of when it is created. The ParDo finds the max value in the iterable and wants to use its timestamp as the output timestamp. For example, the timestamp of the GroupByKey output might be 11 AM, but the timestamp of the max value might be 10:30 AM. Is it possible for the user-defined ParDo to rewind back the timestamp to 10:30 AM? As the runner knows the current watermark, should there be any API for the runner to notify the app of the allowedTimestampSkew? Thanks, Shen
