Use master view's session when creating form

Needed when allowing create for models from non-rattail database

tailbone/forms/alchemy.py

@@ -54,10 +54,11 @@ class AlchemyForm(Object):
 
     allow_successive_creates = False
 
-    def __init__(self, request, fieldset, **kwargs):
+    def __init__(self, request, fieldset, session=None, **kwargs):
         super(AlchemyForm, self).__init__(**kwargs)
         self.request = request
         self.fieldset = fieldset
+        self.session = session
 
     def _get_readonly(self):
         return self.fieldset.readonly
@@ -82,7 +83,7 @@ class AlchemyForm(Object):
 
     def save(self):
         self.fieldset.sync()
-        Session.flush()
+        self.session.flush()
 
     def validate(self):
         self.fieldset.rebind(data=self.request.params)

tailbone/views/master.py

@@ -949,6 +949,7 @@ class MasterView(View):
         else:
             kwargs.setdefault('cancel_url', self.get_action_url('view', instance))
         factory = kwargs.pop('factory', forms.AlchemyForm)
+        kwargs.setdefault('session', self.Session())
         form = factory(self.request, fieldset, **kwargs)
         form.readonly = self.viewing
         return form