Dave Using Wait/Notify would ensure you only have one message in flight at a time (or it can/should). But the message will be ack'd before processed.
For Kafka and some of these message queue mechanisms if we want to offer a 'do not ack until the whole flow is done' behavior we should update the processors to allow for that and actually this is a great use case for the nifi-fn/stateless work that SamH in the community has been talking about. Thanks On Fri, May 17, 2019 at 12:30 PM David Gallagher < dgallag...@cleverdevices.com> wrote: > Hi – I have a requirement to read one message off RabbitMQ and fully > process that message before I take another message off the queue. I found > some great guidance to setting up a ‘traffic light’ pattern here ( > https://gist.github.com/ijokarumawak/9e1a4855934f2bb9661f88ca625bd244), > but it won’t work for my process because the Notify will get triggered by > the GenerateFlowFile before the long-running process triggers, which will > put two or more messages into the process at once. The documentation for > Notify makes reference to using a 0 value in Signal Counter Delta to > simulate ‘open-close-gate’ flow control, which sounds like what I’m looking > for. Can someone point me in the right direction? > > > > Thanks, > > > > Dave > > > > >
