Ticket #6984: load_session_before_save.diff

django/contrib/sessions/backends/base.py

@@ -217 +217 @@
-        """
-        Saves the session data.
-        """
+        # Avoid race conditions, see #6984. Make sure the session dict is
+        # loaded into memory before saving it back.
+        self._get_session()
+        self._save()
+
+    def _save(self):
+        """
+        The actual saving function that has to be overridden by backends.
+        """
-        raise NotImplementedError
-
-    def delete(self, session_key):

django/contrib/sessions/backends/file.py

@@ -60 +60 @@
-            pass
-        return session_data
-
-
+_
-        try:
-            f = open(self._key_to_file(self.session_key), "wb")
-            try:

django/contrib/sessions/backends/cache.py

@@ -13 +13 @@
-        session_data = self._cache.get(self.session_key)
-        return session_data or {}
-
-
+_
-        self._cache.set(self.session_key, self._session, self.get_expiry_age())
-
-    def exists(self, session_key):

django/contrib/sessions/backends/db.py

@@ -36 +36 @@
-            return False
-        return True
-
-
+_
-        Session.objects.create(
-            session_key = self.session_key,
-            session_data = self.encode(self._session),