> On 14.09.2012 15:19, Christopher Nelson wrote: >> Is there >> some tutorial or other documentation that will tell me how listeners >> interact with the system and with each other? > > One place where I've been trying to document such things is in [1]. > Unfortunately the ITicketChangeListener page is not up yet.
I appreciate you efforts and have been there a few times. Thanks. > I'm not aware of any other such resource. Unless the Trac source code > counts. :) Of course it does. And I had seen where it gets invoked. But more broadly, I don't know if Trac gets executed in a single thread (so only one instance of my listener could be active at a time) or if, say, each user gets a thread in the server and multiple saves can fight. >... >> Here's what I'm trying to do: when a field related to scheduling >> tickets changes, do a minimal schedule recalculation. So, if the >> estimate for a ticket change from 8 hours to 16, any following work >> will start a day later or this task will start a day earlier. In the >> latter case, I'll do all my calculations then have a new start date >> for the ticket that the listener got invoked for. When I save that >> change -- inside the listener -- what happens? > > All ITicketChangeListener.ticket_changed() implementations get called in a > loop at the end of Ticket.save_changes() [2]. Right. I've seen that. > There is no special mechanism to handle reentrancy. ITicketChangeListener is > not meant to be used in situations where the ticket gets "manipulated" > (="changed before saving"). Instead you should use > ITicketManipulator.validate_ticket(). Well, I'd argue that I'm not trying to manipulate the ticket as, for example, I think EstimationTools changes an estimate of "8" to "8.0". I'm trying to react to changes in some fields to propagate changes to other tickets (and, fairly often I guess, change additional fields in the current ticket). You could argue that a manipulator could: 1) reschedule everything and save all other tickets, 2) set the new schedule values in the current ticket. But that seems awkward. > The ITicketManipulator documentation page [3] already exists. Improvements > are of course appreciated. >... That's beautiful. Thank you. I have not comments right now because I just skimmed it and don't have an immediate need. -- You received this message because you are subscribed to the Google Groups "Trac Development" group. To post to this group, send email to trac-dev@googlegroups.com. To unsubscribe from this group, send email to trac-dev+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/trac-dev?hl=en.
