After refreshing a product, Zope 2 uses the following stanza in
App.RefreshFuncs.autoRefresh() to let the ZODB know that it should
invalidate its pickle caches:
... refresh products
from ZODB import Connection
That way, persistent objects will use the newly reimported classes
instead of continuing to use the old, no longer current classes.
For grok I tried to implement the same mechanism and copied that code
almost verbatimly, only to find out it doesn't seem to work. Persistent
objects will still be instances of the classes that should have been
thrown away during the re-import of modules.
Testing product refresh with both Zope 2.9 and 2.10 produces errors for
me while Zope 2.8 works, which leads me to the assumption that a cache
invalidation bug was introduced after ZODB 3.4. Is anybody else seeing
this? I'm a bit surprised nobody else has complained about this so far...
Help with tracking this down would be greatly appreciated.
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