N°1681 - Add new trigger for attachment creation

[accognet]

Create a new trigger "on object's attachment creation"

[Molkobain]

Discussed IRL with Anne-Catherine, several things to change:

Point 1
Hacking the standard "Trigger on update" with JS to remove the "Attachment" class from proposed value doesn't seem like a good option.

Instead we would rather improve the \AttributeClass class to add a class_exclusion_list like we do for \AttributeClassAttCodeSet with attribute_definition_exclusion_list. Check with @rquetiez or @eespie , they can guide you.

Point 2
The way it is currently done, you can't limit the trigger to attachments of a specific class only, which is most likely something we'll want to do.

Point 3
Because of the previous points, you can't rely on the ComputeValues method and the fact it derived from the standard TriggerOnObjectUpdate, you'll need to call your trigger when attachments are finalized. We might want to add an event for that actually, check with Eric.

[Hipska]

May I ask why the existing triggers aren’t sufficient?

[accognet]

It does but to get an attachment creation notification, we need to create an "on object update" trigger on the attachment with the temp_id field. It's not really logical.

[Molkobain]

During the technical review, we'll need to discuss the possible impacts of adding the class_exclusion_list property on the existing AttributeClass attribute:

• Can it be omitted in an AttributeClass instantiation (existing customizations using that type of attribute)
• Create the corresponding Designer ticket
• ...