Hi there,

We just noticed that some objects were not being cataloged correctly. After a lot of debugging, we noticed the following:


The IntId utility wouldn't find the unique id for an object when a modified event was sent. As a result, it wasn't being indexed.

We figured out that there was an odd difference between the object that came into the IntId utility (through a modification event) and the object that we could take from the folder: the one taken directly from the folder has a __name__ and __parent__. Even though the memory address looked the same when using repr(), they were not identical. As a result the int id couldn't be found.

Finally with some help from Stephan Richter giving us the clue that this __name__ and __parent__ information could only be lost if LocationProxy is in play, we figured out what what we think is going on:

What is stored in the ZODB are LocationProxy wrapped objects. The location proxy wrappers get a unique id reference in the IntId utility, not the objects themselves. Now when you send an ObjectModificationEvent from one the document's *own methods*, the event is sent with as payload to catalog something that is not proxy wrapped. This means that the int id can never be found for this object, and thus the reindexing cannot take place properly.

This basically means that LocationProxy wrapped objects cannot reliably respond correctly to ObjectModificationEvents, and thus won't be cataloged correctly. If the ObjectModifiedEvent is sent by methods inside the object itself, things will fail, if the ObjectModifiedEvent is sent by code elsewhere, they'll likely work.

This is all fixed by subclassing Contained, but the catalog not working reliably for LocationProxy wrapped objects sounds scary. You could do something with the IntId utility automatically un-location-proxy-wrapping the objects if necessary, but that would mean that what is stored wouldn't know its location anymore, which would also be bad.

Regards,

Martijn

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