Hi Andrew, thanks for the link, I looked into the wait/notify mechanism yesterday and found that one wait processor actually could only wait for exactly one notify signal, but my case is like this: Processor A, B and C， C has to wait for both flow files from A and B conditionally, if A and B all outputs flow files, C needs to wait for both flow files and use both flow files to update data in C; if either A or B doesn't emit flowfile, C also needs to use all incoming flow files to update data I could know in advance in up-stream processors whether A and B would produce flowfiles, but I don't know if it's feasible with NIFI to implement the following: 1. use wait/notify to wait for multiple different signals(do I have to use multiple wait processor chained in a flow to do it?) 2. use wait/notify to conditionally wait for a signal
Thanks, Ben 2017-05-10 11:49 GMT+08:00 Andrew Psaltis <[email protected]>: > Hi, > I think the new Wait / Notify processors, can be used to solve this > problem. Koji has a great blog post on it [1]. > > > [1] http://ijokarumawak.github.io/nifi/2017/02/02/nifi-notify-batch/ > > Thanks, > Andrew > > On Tue, May 9, 2017 at 11:43 PM, 尹文才 <[email protected]> wrote: > >> Hi guys, I'm currently using NiFi to do some ETL work and I need to >> handle the following problem: >> >> for example I have 3 self-defined processor A, B and C. >> all of them contain logic to incrementally update a database table. the >> table in C is created by table in A join table in B, so C depends on the >> flowfiles from A and B. >> >> So my question is is there a way for C to wait for both flowfiles from A >> and B >> to arrive and then start the work in C? Thanks. >> > > > > -- > Thanks, > Andrew > > Subscribe to my book: Streaming Data <http://manning.com/psaltis> > <https://www.linkedin.com/pub/andrew-psaltis/1/17b/306> > twiiter: @itmdata <http://twitter.com/intent/user?screen_name=itmdata> >
