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From Toivo Adams <>
Subject Re: [DISCUSS] Feature proposal: "Function Groups" and wormholes
Date Sun, 09 Aug 2015 12:04:35 GMT
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.


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