Be resilient if not all middleware run.

Fix #129.

5 files changed, 30 insertions, 20 deletions

diff --git a/debug_toolbar/panels/headers.py b/debug_toolbar/panels/headers.py
index 36ecf3c..2a41081 100644
--- a/debug_toolbar/panels/headers.py
+++ b/debug_toolbar/panels/headers.py
@@ -49,13 +49,15 @@ class HeaderDebugPanel(DebugPanel):
             self.request_headers['Cookie'] = '=> see Request Vars panel'
         self.environ = OrderedDict(
             (k, v) for (k, v) in wsgi_env if k in self.environ_filter)
+        self.record_stats({
+            'request_headers': self.request_headers,
+            'environ': self.environ,
+        })
 
     def process_response(self, request, response):
         self.response_headers = OrderedDict(sorted(response.items()))
         self.record_stats({
-            'request_headers': self.request_headers,
             'response_headers': self.response_headers,
-            'environ': self.environ,
         })
 
 
diff --git a/debug_toolbar/panels/request_vars.py b/debug_toolbar/panels/request_vars.py
index dc5b7b0..b5e7070 100644
--- a/debug_toolbar/panels/request_vars.py
+++ b/debug_toolbar/panels/request_vars.py
@@ -23,14 +23,11 @@ class RequestVarsDebugPanel(DebugPanel):
     def title(self):
         return _('Request Vars')
 
-    def process_request(self, request):
-        self.request = request
-
     def process_response(self, request, response):
         self.record_stats({
-            'get': [(k, self.request.GET.getlist(k)) for k in sorted(self.request.GET)],
-            'post': [(k, self.request.POST.getlist(k)) for k in sorted(self.request.POST)],
-            'cookies': [(k, self.request.COOKIES.get(k)) for k in sorted(self.request.COOKIES)],
+            'get': [(k, request.GET.getlist(k)) for k in sorted(request.GET)],
+            'post': [(k, request.POST.getlist(k)) for k in sorted(request.POST)],
+            'cookies': [(k, request.COOKIES.get(k)) for k in sorted(request.COOKIES)],
         })
         view_info = {
             'view_func': _('<no view>'),
@@ -39,7 +36,7 @@ class RequestVarsDebugPanel(DebugPanel):
             'view_urlname': 'None',
         }
         try:
-            match = resolve(self.request.path)
+            match = resolve(request.path)
             func, args, kwargs = match
             view_info['view_func'] = get_name_from_obj(func)
             view_info['view_args'] = args
@@ -50,8 +47,8 @@ class RequestVarsDebugPanel(DebugPanel):
             pass
         self.record_stats(view_info)
 
-        if hasattr(self.request, 'session'):
+        if hasattr(request, 'session'):
             self.record_stats({
-                'session': [(k, self.request.session.get(k))
-                            for k in sorted(self.request.session.keys(), key=force_text)]
+                'session': [(k, request.session.get(k))
+                            for k in sorted(request.session.keys(), key=force_text)]
             })
diff --git a/debug_toolbar/panels/template.py b/debug_toolbar/panels/template.py
index 711193e..172765a 100644
--- a/debug_toolbar/panels/template.py
+++ b/debug_toolbar/panels/template.py
@@ -120,14 +120,11 @@ class TemplateDebugPanel(DebugPanel):
         num_templates = len(self.templates)
         return _('Templates (%(num_templates)s rendered)') % {'num_templates': num_templates}
 
-    def process_request(self, request):
-        self.request = request
-
     def process_response(self, request, response):
         context_processors = dict(
             [
                 ("%s.%s" % (k.__module__, k.__name__),
-                    pformat(k(self.request))) for k in get_standard_processors()
+                    pformat(k(request))) for k in get_standard_processors()
             ]
         )
         template_context = []
diff --git a/debug_toolbar/panels/timer.py b/debug_toolbar/panels/timer.py
index ac8a808..9a0fef3 100644
--- a/debug_toolbar/panels/timer.py
+++ b/debug_toolbar/panels/timer.py
@@ -32,8 +32,10 @@ class TimerDebugPanel(DebugPanel):
             self._start_rusage = resource.getrusage(resource.RUSAGE_SELF)
 
     def process_response(self, request, response):
-        stats = {'total_time': (time.time() - self._start_time) * 1000}
-        if self.has_resource:
+        stats = {}
+        if hasattr(self, '_start_time'):
+            stats['total_time'] = (time.time() - self._start_time) * 1000
+        if hasattr(self, '_start_rusage'):
             self._end_rusage = resource.getrusage(resource.RUSAGE_SELF)
             stats['utime'] = 1000 * self._elapsed_ru('ru_utime')
             stats['stime'] = 1000 * self._elapsed_ru('ru_stime')
@@ -62,15 +64,17 @@ class TimerDebugPanel(DebugPanel):
     def nav_subtitle(self):
         stats = self.get_stats()
 
-        if self.has_resource:
+        if hasattr(self, '_start_rusage'):
             utime = self._end_rusage.ru_utime - self._start_rusage.ru_utime
             stime = self._end_rusage.ru_stime - self._start_rusage.ru_stime
             return _('CPU: %(cum)0.2fms (%(total)0.2fms)') % {
                 'cum': (utime + stime) * 1000.0,
                 'total': stats['total_time']
             }
-        else:
+        elif 'total_time' in stats:
             return _('TOTAL: %0.2fms') % stats['total_time']
+        else:
+            return ''
 
     def title(self):
         return _('Time')
diff --git a/tests/test_integration.py b/tests/test_integration.py
index 4bb0d38..a80f50c 100644
--- a/tests/test_integration.py
+++ b/tests/test_integration.py
@@ -12,6 +12,7 @@ from debug_toolbar.middleware import DebugToolbarMiddleware, show_toolbar
 from debug_toolbar.panels.request_vars import RequestVarsDebugPanel
 
 from .base import BaseTestCase
+from .views import regular_view
 
 
 rf = RequestFactory()
@@ -117,6 +118,15 @@ class DebugToolbarTestCase(BaseTestCase):
         self.assertEqual(stats['view_kwargs'], 'None')
         self.assertEqual(stats['view_func'], '<no view>')
 
+    # Django doesn't guarantee that process_request, process_view and
+    # process_response always get called in this order.
+
+    def test_middleware_view_only(self):
+        DebugToolbarMiddleware().process_view(self.request, regular_view, ('title',), {})
+
+    def test_middleware_response_only(self):
+        DebugToolbarMiddleware().process_response(self.request, self.response)
+
 
 @override_settings(DEBUG=True)
 class DebugToolbarIntegrationTestCase(TestCase):