Fix triggering an extra SQL query via the auth context processor.

Fixed by moving the template panel's context_processor introspection to the
content method so this happens at the process_response time instead of at
process_request time.  Since context processors _were_ happening at the
process_response end, it was triggering the query
`user.get_and_delete_messages()` which was also getting triggered separately if
used in templates (i.e. the admin templates) resulting in duplicate queries
showing up in the toolbar.

1 files changed, 8 insertions, 4 deletions

diff --git a/debug_toolbar/panels/template.py b/debug_toolbar/panels/template.py
index fa85cb8..7dc7b06 100644
--- a/debug_toolbar/panels/template.py
+++ b/debug_toolbar/panels/template.py
@@ -48,11 +48,15 @@ class TemplateDebugPanel(DebugPanel):
         return ''
 
     def process_request(self, request):
-        self.context_processors = dict(
-            [("%s.%s" % (k.__module__, k.__name__), pformat(k(request))) for k in get_standard_processors()]
-        )
+        self.request = request
 
     def content(self):
+        context_processors = dict(
+            [
+                ("%s.%s" % (k.__module__, k.__name__),
+                    pformat(k(self.request))) for k in get_standard_processors()
+            ]
+        )
         template_context = []
         for i, d in enumerate(self.templates):
             info = {}
@@ -73,6 +77,6 @@ class TemplateDebugPanel(DebugPanel):
         context = {
             'templates': template_context,
             'template_dirs': [normpath(x) for x in settings.TEMPLATE_DIRS],
-            'context_processors': self.context_processors,
+            'context_processors': context_processors,
         }
         return render_to_string('debug_toolbar/panels/templates.html', context)