command-handler and exception in event-handler

Imported from Google Groups
1

When an exception occurs in event-handler, can that exception be
propagated to command-handler?

Thanks,

Jamil

2

Hi Jamil,

when an event handler receives an event, the processing of the command handler is long finished. However, it is possible to have the Command Handler register a listener on the UnitOfWork that takes action when the UoW is rolled back. In the @CommandHandler methods, you can use a second parameter of type UnitOfWork or use the static CurrentUnitOfWork.get() method to obtain the UnitOfWork. Use the registerListener() method to register a listener.

Do note that this is considered bad design in general to solve issues. It relies on everything running synchronously. In general, once an Event is published, it should be considered gone. A listener that fails to process an Event should generally log that somewhere and continue processing.

Hope this helps.
Cheers,

Allard

3

Thank you for the clarification. I'll take of the exceptions in the
event-handler itself.