[sync] What should we do about GUIDs changing?

[Chuck Hagenbuch]

We've started using GUIDs (generic universal ids or somesuch) to refer to
various objects throughout Horde (tasks, notes, etc.) for purposes of external
references (iCalendar files have a GUID for each vevent) and for syncing
support.

However, the way we have them generated right now for most apps is something
like this:

appname:sharename:itemid

sharename is the problem there - what if the user moves a task to a different
tasklist? We *should* be smart enough to still be able to see it's the same
task when we next sync, etc.

So, any ideas on a better way to do this? Should we add an extra field for it to
all our data stores? I'd rather not, where we can avoid it.

One idea: use the task_id directly and leave the sharename out. We could do this
in nag because the task_id will either be a unique id in the nag_tasks table,
or a category_id, which will be unique across all tasklists. Though, it occurs
to me that the way the code is written, we delete and recreate the task when we
move it between tasklists, so that'd have to be fixed too.

Other suggestions?

-chuck

--
"Regard my poor demoralized mule!" - Juan Valdez