Implement a more throughough cache-flush mechanism. This makes sure to flush foreignkey cache relations for objects not affected by flushing (normally objects with an NAttribute stored in them). Without ForeignKey flushing, the location of such objects would remain cached and drift out of sync, leading to content caches in turn desyncing. Resolves #1064.

evennia/objects/models.py

@@ -22,7 +22,7 @@ from django.core.exceptions import ObjectDoesNotExist
 from evennia.typeclasses.models import TypedObject
 from evennia.objects.manager import ObjectDBManager
 from evennia.utils import logger
-from evennia.utils.utils import (make_iter, dbref, lazy_property, calledby)
+from evennia.utils.utils import (make_iter, dbref, lazy_property)
 
 
 class ContentsHandler(object):
@@ -51,10 +51,8 @@ class ContentsHandler(object):
         Re-initialize the content cache
 
         """
-        #print "__init__", self.obj, calledby()
         self._pkcache.update(dict((obj.pk, None) for obj in
                             ObjectDB.objects.filter(db_location=self.obj) if obj.pk))
-        #print "init contentscache: self._pkcache:", self.obj, self._pkcache, id(self._pkcache), id(self)
 
     def get(self, exclude=None):
         """
@@ -70,15 +68,12 @@ class ContentsHandler(object):
         if exclude:
             pks = [pk for pk in self._pkcache if pk not in [excl.pk for excl in make_iter(exclude)]]
         else:
-            #print calledby()
-            #print "get: self._pkcache", self.obj, self._pkcache, id(self._pkcache), id(self)
             pks = self._pkcache
         try:
             return [self._idcache[pk] for pk in pks]
         except KeyError, err:
             # this can happen if the idmapper cache was cleared for an object
             # in the contents cache. If so we need to re-initialize and try again.
-            #print "content_cache.get keyerror:", err, self._pkcache, self._idcache
             self.init()
             try:
                 return [self._idcache[pk] for pk in pks]
@@ -96,7 +91,6 @@ class ContentsHandler(object):
 
         """
         self._pkcache[obj.pk] = None
-        #print "add self._pkcache:", self.obj, obj, obj.pk, self._pkcache
 
     def remove(self, obj):
         """
@@ -107,7 +101,6 @@ class ContentsHandler(object):
 
         """
         self._pkcache.pop(obj.pk, None)
-        #print "remove self._pkcache", self.obj, obj, obj.pk, self._pkcache
 
     def clear(self):
         """
@@ -116,7 +109,6 @@ class ContentsHandler(object):
         """
         self._pkcache = {}
         self.init()
-        #print "clear _pkcache", self.obj, self._pkcache
 
 #------------------------------------------------------------
 #
@@ -272,12 +264,10 @@ class ObjectDB(TypedObject):
             # remove the safe flag
             del self._safe_contents_update
 
-            #print "location_set:", self.key, old_location, self.db_location
             # update the contents cache
             if old_location:
                 old_location.contents_cache.remove(self)
             if self.db_location:
-                #print "cache add:", self.db_location, self
                 self.db_location.contents_cache.add(self)
 
         except RuntimeError:

evennia/typeclasses/models.py

@@ -386,6 +386,14 @@ class TypedObject(SharedMemoryModel):
                 False, don't flush and expect this object to handle
                 the flushing on its own.
 
+        Notes:
+            The default implementation relies on being able to clear
+            Django's Foreignkey cache on objects not affected by the
+            flush (notably objects with an NAttribute stored). We rely
+            on this cache being stored on the format "_<fieldname>_cache".
+            If Django were to change this name internally, we need to
+            update here (unlikely, but marking just in case).
+
         """
         if self.nattributes.all():
             # we can't flush this object if we have non-persistent
@@ -393,6 +401,12 @@ class TypedObject(SharedMemoryModel):
             # we try to flush as many references as we can.
             self.attributes.reset_cache()
             self.tags.reset_cache()
+            # flush caches for all related fields
+            for field in self._meta.fields:
+                name = "_%s_cache" % field.name
+                if field.is_relation and name in self.__dict__:
+                    # a foreignkey - remove its cache
+                    del self.__dict__[name]
             return False
         # a normal flush
         return True

evennia/utils/idmapper/models.py

@@ -321,8 +321,6 @@ class SharedMemoryModel(with_metaclass(SharedMemoryModelBase, Model)):
         else:
             cls.__dbclass__.__instance_cache__ = dict((key, obj) for key, obj in cls.__dbclass__.__instance_cache__.items()
                                                       if not obj.at_idmapper_flush())
-            for ins in cls.__dbclass__.__instance_cache__.itervalues():
-                ins.refresh_from_db()
     #flush_instance_cache = classmethod(flush_instance_cache)
 
     # per-instance methods
@@ -349,8 +347,6 @@ class SharedMemoryModel(with_metaclass(SharedMemoryModelBase, Model)):
         if pk:
             if force or self.at_idmapper_flush():
                 self.__class__.__dbclass__.__instance_cache__.pop(pk, None)
-            else:
-                self.refresh_from_db()
 
     def delete(self, *args, **kwargs):
         """