nifi-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Joe Witt <>
Subject Re: [DISCUSS] Feature proposal: "Function Groups" and wormholes
Date Sun, 09 Aug 2015 13:27:09 GMT

I think from your response you did understand it quite well.  I'll try
to turn this and a series of other features/concepts into a series of
wiki pages so it can be more readily consumed, improved, and commented


On Sun, Aug 9, 2015 at 8:04 AM, Toivo Adams <> wrote:
> Not sure I understand 'wormhole' concept correctly.
> We use a lot of request-response type of processing.
> Processing pipeline contain several processors.
> Processing is done mostly sequentially (and same parts parallel).
> During processing anything can happen. But our goal is to send always
> responds back.
> In case of errors response contains errors data.
> There can be different types of problems; some are warnings, some notices,
> some errors and some fatal errors.
> In case of fatal errors we stop processing automatically and jump directly
> to so called ‘error flow’. (subflow)
> Error flow responsibility is to create response which contains errors and
> send response back to requestor.
> Error flow may also contain some special purpose processors – collect some
> data for report, alert monitoring, etc.
> Now 'wormhole' is very helpful. It’s annoying to add explicit connections to
> all business processors. Also this reduces readability.
> For us flow should readable and understandable from business point of view.
> And low level technical behavior should be handled ‘behind the scenes’.
> Ideally business processors should not have ‘redirect to error flow’ output
> (relationship) at all.
> At the same time I think 'wormhole' should be used very carefully. Only when
> really needed.
> Otherwise it may be source of weird bugs and it is hard to follow what is
> going on.
> Thanks
> toivo
> --
> View this message in context:
> Sent from the Apache NiFi (incubating) Developer List mailing list archive at

View raw message