Re: [Openflow-dev] Exception Handling

[Daniele T. <d.t...@ic...>]

On Wednesday 28 January 2004 13:06, Mikel Larreategi wrote:
> Hi:
>
> How does exception handling work in OpenFlow?
> I'm trying to understand it but I can't ;)
>
> When I fallout a workitem I have 2 possibilities:
>    - End Fallout: Is this to recover workitem's original status in the
> activity it was before de fallout?

This ends the handling if the exceptional workitem. 


>    - Fallin: With this I can put the workitem in the activity I want,
> but it creates a new workitem? :S What happens with the "original" one?
> It seems to be still in fallout, but then can it follow the "original" way?

This creates new workitems (yes, even more than one if called more than once) 
in any activity of the workflow. 

So this brings to the following handling example:

A workitem (say 1) in activity A goes in exceptional state (fallout). You can 
take it resume its course in activity B (workitem 2) and C (workitem 3) 
calling the fallin API twice, once specifying B and once specifying C 
(thereby creating a parallel flow). To signal the ending of the exceptional 
state you call the end-fallout API: workitem 1 will cease being exceptional 
and thereby can't generate any new workitem. Flow will resume from activities 
B and C (the instance being "alive" and running with workitems 2 and 3).

This means, in general:

- workitem goes fallout
- resume workitem as many times and wherever you want using fallin
- end the handling signaling an end-fallout


> Regards,
>
> Mikel Larreategi
> lar...@ei...

Cheers,
	Daniele

-- 
Daniele Tarini - Research & Development - Icube S.r.l.
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