Use ZODB new class_factory parameter to register class factory

Author: perrinjerome

CHANGES.rst

@@ -14,6 +14,10 @@ https://github.com/zopefoundation/Zope/blob/5.x/CHANGES.rst.
 
 - Update to newest compatible versions of dependencies.
 
+- Use ZODB new ``class_factory`` parameter to fix registration of ZODB class
+  factory sometimes not beeing effective.
+  See `ZODB issue #420 <https://github.com/zopefoundation/ZODB/issues/420>`_.
+
 
 6.0 (2026-03-04)
 ----------------

docs/locale/ja/LC_MESSAGES/operation.po

@@ -1657,19 +1657,6 @@ msgid ""
 "specify the connection class."
 msgstr ""
 
-#: ../../Schema
-msgid ""
-"class-factory (Zope2.Startup.datatypes.importable_name)  (default: "
-"Zope2.Startup.datatypes.simpleClassFactory)"
-msgstr ""
-
-#: ../../description:1
-msgid ""
-"Change the class factory function a database uses on a per-database basis"
-" to support different class factory policy. Use a Python dotted-path name"
-" to specify the class factory function."
-msgstr ""
-
 #: ../../Schema
 msgid "container-class (string)"
 msgstr ""

src/Zope2/App/startup.py

@@ -79,6 +79,7 @@ def startup():
         getattr(configuration, 'testinghome', None),
         configuration.instancehome,
     ]
+    from .ClassFactory import ClassFactory
     for location in custom_locations:
         if not location:
             continue
@@ -91,8 +92,10 @@ def startup():
                 DB = module.DB
                 databases.update(getattr(DB, 'databases', {}))
                 DB.databases = databases
+                DB.classFactory = ClassFactory
             else:
-                DB = ZODB.DB(module.Storage, databases=databases)
+                DB = ZODB.DB(module.Storage, databases=databases,
+                             class_factory=ClassFactory)
 
             break
     else:
@@ -116,9 +119,6 @@ def startup():
     Zope2.DB = DB
     Zope2.opened.append(DB)
 
-    from . import ClassFactory
-    DB.classFactory = ClassFactory.ClassFactory
-
     # "Log on" as system user
     newSecurityManager(None, AccessControl.users.system)
 

src/Zope2/Startup/datatypes.py

@@ -135,15 +135,16 @@ class ZopeDatabase(ZODBDatabase):
 
     def createDB(self, database_name, databases):
         self.config.database_name = database_name
+        if self.config.class_factory is None:
+            from Zope2.App.ClassFactory import ClassFactory
+            self.config.class_factory = ClassFactory
         return ZODBDatabase.open(self, databases)
 
     def open(self, database_name, databases):
         DB = self.createDB(database_name, databases)
         if self.config.connection_class:
             # set the connection class
             DB.klass = self.config.connection_class
-        if self.config.class_factory is not None:
-            DB.classFactory = self.config.class_factory
         return DB
 
     def getName(self):
@@ -257,10 +258,3 @@ def getName(self, mount_path):
         if name is None:
             self._mountPathError(mount_path)
         return name
-
-
-def simpleClassFactory(jar, module, name, _silly=('__doc__',), _globals={}):
-    """Class factory.
-    """
-    m = __import__(module, _globals, _globals, _silly)
-    return getattr(m, name)

src/Zope2/Startup/wsgischema.xml

@@ -61,15 +61,6 @@
       </description>
     </key>
 
-   <key name="class-factory" datatype=".importable_name"
-        default="Zope2.Startup.datatypes.simpleClassFactory">
-      <description>
-       Change the class factory function a database uses on a
-       per-database basis to support different class factory policy.
-       Use a Python dotted-path name to specify the class factory function.
-      </description>
-    </key>
-
     <key name="container-class" datatype="string">
       <description>
        Change the container class a (mounted) database uses on a