17 Oct
2018
17 Oct
'18
10:47 a.m.
On 10/17/18 10:35 AM, Guillaume Delhumeau wrote:
I'm OK.
<OFF TOPIC>
I'm just thinking about an other particular case:
Imagine you have 3 event listeners (A, B, C):
- A receives the event and perform some actions (saving something in the
database).
- B receives the event and cancels it
- C don't receive the event because it had been canceled
However, we may want to resend some infos to listener A so it can rollback
its actions (otherwise we end up with bad info in the database).
Do we have a strategy for this?
I don't think we have a strategy for that, but we might add a new method
in EventListener:
onRollback(CancelableEvent canceledEvent, Object source, Object data)
and store somewhere the list of called listener to be able to call their
rollback method if the event has been cancelled. Should do the trick, WDYT?
</OFF TOPIC>
Le mer. 17 oct. 2018 à 09:09, Thomas Mortagne <thomas.mortagne(a)xwiki.com> a
écrit :
--
Simon Urli
Software Engineer at XWiki SAS
simon.urli(a)xwiki.com
More about us at http://www.xwiki.com
+1 to stopping event propagation when it's
cancelled
On Tue, Oct 16, 2018 at 6:07 PM Simon Urli <simon.urli(a)xwiki.com> wrote:
Hi everyone,
the current behaviour of the ObservationManager is to always triggers
the listeners if it matches the events.
Now regarding the CancelableEvents, the match is only done on the type
of the event and some given filter rules, but never with its cancel
status: if an event is cancelled, the matching listeners are always
triggered.
I propose to change that behaviour, to trigger listeners only if the
CancelableEvents are not canceled: basically, a cancelled event wouldn't
match any listener.
My primary reason for wanting that change is that the current behaviour
led to a bad UX: if an event triggers multiple questions, no matter if
one is cancelled, all questions will be asked to the user.
Do you know if the current behaviour is required at some places?
Else do you agree on changing it?
Simon
--
Simon Urli
Software Engineer at XWiki SAS
simon.urli(a)xwiki.com
More about us at http://www.xwiki.com
--
Thomas Mortagne