[storm] why weakrefdict for cache?

[Bernd Dorn]

Hi all

we use storm with zope (version .10) and discovered that the  
store._cache attribute never caches, because the weakrefs are gone  
immediatly

we changed the implementation to use a normal dict, and do a  
self._cache.clear() if an invalidate(None) is issued. which is done  
on commit and rollback. this makes sure there are no objects  
referenced after a transaction

what about integrating this into storm?

cheers, bernd

here is the diff:

bd:~/sandbox/storm $ bzr diff storm/store.py
=== modified file 'storm/store.py'
--- storm/store.py      2007-08-15 15:41:25 +0000
+++ storm/store.py      2007-08-31 10:20:20 +0000
@@ -64,7 +64,7 @@
          @param database: The L{storm.database.Database} instance to  
use.
          """
          self._connection = database.connect()
-        self._cache = WeakValueDictionary()
+        self._cache = {} #WeakValueDictionary()
          self._dirty = {}
          self._order = {} # (info, info) = count

@@ -350,6 +350,8 @@
          if invalidate:
              for obj_info in obj_infos:
                  self._run_hook(obj_info, "__storm_invalidated__")
+        if obj is None:
+            self._cache.clear()

      def add_flush_order(self, before, after):
          """Explicitly specify the order of flushing two objects.