Hi Nick,
A couple of days ago we had an incident where a runaway process on a server cause it to become largely unresponsive. This server also holds the Magma repository. It appears that as a result of Magma operating through this incident, a commit on a domain object succeeded, but the index update failed, so the index continued to reflect the old state of the object. (I can't prove this is the cause, but it seems to me likely.)
Hm, this should never happen. Magma writes to the DB atomically, including index updates. Strange.
Hitting Google for advice on fixing the Magma index, I found a thread on this list [1] where the given solution to this sort of index problem is to remove and re-add the object to the collection. However, when I remove the object from the collection, it doesn't get removed from the index (presumably because the index entry removal depends upon the state of the object being correspondent, which of course in this case, it isn't.)
Yes, that appears to be true. See MagmaCollectionManager>>#processRemovesIn: for the method that actually does this. I wonder if temporarily removing the "didRemove" guard would have worked for you? Hm, I'm actually wondering whether that guard is really necessary..
On re-adding the object to the collection, it gets indexed with its correct state, but this is in *addition* to the old index entry. So that didn't fix my problem.
Just a note: Objects can be added multiple times to a MagmaCollection, so if it was in there more than once it would be indexed more than once too. Doesn't sound like that was the case this time but, just fyi.
I did subsequently fix it by reverting the state of the domain object to match the index, then progressing the object forward through its normal process, successfully updating the index as it went.
So, the questions are: 1 - Is there another way of fixing the problem, that I missed? 2 - Ought there to be clearly defined interfaces for forcing in & out particular index entries, or forcing entire index rebuilds?
You could do a #removeIndexNamed: followed by #addIndex: to force a full rebuild.
- Chris