Stop sharing unsafely a context dict across threads.

Panels that need to share data with other panels shall do it through the
record_stats / get_stats API. Statistics are automatically pushed to the
template context.

Fix #450.

Author: aaugustin

debug_toolbar/panels/__init__.py

@@ -9,16 +9,10 @@ class Panel(object):
     """
     Base class for panels.
     """
-
-    # We'll maintain a local context instance so we can expose our template
-    # context variables to panels which need them. (But see issue #450.)
-    context = {}
-
-    # Private panel methods
-
-    def __init__(self, toolbar, context={}):
+    def __init__(self, toolbar):
         self.toolbar = toolbar
-        self.context.update(context)
+
+    # Private panel properties
 
     @property
     def panel_id(self):
@@ -81,9 +75,7 @@ def content(self):
         template's context.
         """
         if self.has_content:
-            context = self.context.copy()
-            context.update(self.get_stats())
-            return render_to_string(self.template, context)
+            return render_to_string(self.template, self.get_stats())
 
     # URLs for panel-specific views
 

debug_toolbar/panels/timer.py

@@ -45,9 +45,7 @@ def content(self):
             (_('Elapsed time'), _('%(total_time)0.3f msec') % stats),
             (_('Context switches'), _('%(vcsw)d voluntary, %(ivcsw)d involuntary') % stats),
         )
-        context = self.context.copy()
-        context.update({'rows': rows})
-        return render_to_string(self.template, context)
+        return render_to_string(self.template, {'rows': rows})
 
     def process_request(self, request):
         self._start_time = time.time()

debug_toolbar/toolbar.py

@@ -20,10 +20,9 @@ class DebugToolbar(object):
     def __init__(self, request):
         self.request = request
         self.config = dt_settings.CONFIG.copy()
-        self.template_context = {'toolbar': self}
         self._panels = SortedDict()
         for panel_class in self.get_panel_classes():
-            panel_instance = panel_class(self, context=self.template_context)
+            panel_instance = panel_class(self)
             self._panels[panel_instance.panel_id] = panel_instance
         self.stats = {}
         self.store_id = None
@@ -58,8 +57,7 @@ def render_toolbar(self):
         """
         if not self.should_render_panels():
             self.store()
-        context = self.template_context.copy()
-        return render_to_string('debug_toolbar/base.html', context)
+        return render_to_string('debug_toolbar/base.html', {'toolbar': self})
 
     # Handle storing toolbars in memory and fetching them later on