What are you trying to do by nacking the message? If your trying to delay the processing of the message till a future time, look at using State & Timers with StatefulDoFn to queue the message for processing at a future time. See this blog for some examples: https://beam.apache.org/blog/2017/02/13/stateful-processing.html If the message is bad/broken in some way and requires manual intervention, you should really deliver to a dead letter queue (DLQ): ReadFromPubSub ----> DecideIfMessageIsBad --YES--> WriteToPubSub(DLQ) \--NO--> ContinueNormalProcessing
On Sun, Jun 11, 2017 at 11:48 PM, Gwilym Evans <[email protected] > wrote: > Hi list, > > When processing a PubsubMessage, is it possible to trigger something to > cause the message to return to the queue? > > That is, to either NACK the message, or just not ACK it? > > I'm using the Java Beam SDK v2.0.0 > > Thanks, > Gwilym > >
