Cleanup sql session after request. ALWAYS!

The cleanup could be missed if the request handling code in
app.py:__call__ exits early (due to exception, or due to
one of those early "return"s).
So to make sure the sql session is cleaned up for real,
wrap the whole thing in a try: finally:.

Also wrote a short tool to test if the session is actually
empty. The tool is currently disabled, but ready to be
used.

diff --git a/mediagoblin/app.py b/mediagoblin/app.py
index 0a57c09101e7db3944b59f10f594ec93aaf6fdb9..b7ca092d2345b32d42188261059cb251ae681482 100644 (file)
--- a/mediagoblin/app.py
+++ b/mediagoblin/app.py
@@ -109,7 +109,7 @@ class MediaGoblinApp(object):
         self.meddleware = [common.import_component(m)(self)
                            for m in meddleware.ENABLED_MEDDLEWARE]
 
-    def __call__(self, environ, start_response):
+    def call_backend(self, environ, start_response):
         request = Request(environ)
 
         ## Routing / controller loading stuff
@@ -184,15 +184,18 @@ class MediaGoblinApp(object):
         for m in self.meddleware[::-1]:
             m.process_response(request, response)
 
-        # Reset the sql session, so that the next request
-        # gets a fresh session
+        return response(environ, start_response)
+
+    def __call__(self, environ, start_response):
+        ## If more errors happen that look like unclean sessions:
+        # self.db.check_session_clean()
+
         try:
+            return self.call_backend(environ, start_response)
+        finally:
+            # Reset the sql session, so that the next request
+            # gets a fresh session
             self.db.reset_after_request()
-        except TypeError:
-            # We're still on mongo
-            pass
-
-        return response(environ, start_response)
 
 
 def paste_app_factory(global_config, **app_config):

diff --git a/mediagoblin/db/sql/open.py b/mediagoblin/db/sql/open.py
index edbf0785a78d03bed3a5db7c06bce62b99a794a5..ce5f06042f8d8f33c95763edf41ebd394bca448f 100644 (file)
--- a/mediagoblin/db/sql/open.py
+++ b/mediagoblin/db/sql/open.py
@@ -37,6 +37,12 @@ class DatabaseMaster(object):
         Session.add(obj)
         Session.flush()
 
+    def check_session_clean(self):
+        for dummy in Session():
+            _log.warn("STRANGE: There are elements in the sql session. "
+                      "Please report this and help us track this down.")
+            break
+
     def reset_after_request(self):
         Session.rollback()
         Session.remove()