Adding a signals panel to display list of signals and their providing arguments

and receivers.  Thanks Alex Gaynor!

Signed-off-by: Rob Hudson <rob@cogit8.org>

1 files changed, 73 insertions, 0 deletions

diff --git a/debug_toolbar/panels/signals.py b/debug_toolbar/panels/signals.py
new file mode 100644
index 0000000..0a75282
--- /dev/null
+++ b/debug_toolbar/panels/signals.py
@@ -0,0 +1,73 @@
+import sys
+
+from django.conf import settings
+from django.core.signals import request_started, request_finished, \
+    got_request_exception
+from django.db.backends.signals import connection_created
+from django.db.models.signals import class_prepared, pre_init, post_init, \
+    pre_save, post_save, pre_delete, post_delete, post_syncdb
+from django.dispatch.dispatcher import WEAKREF_TYPES
+from django.template.loader import render_to_string
+
+from debug_toolbar.panels import DebugPanel
+
+class SignalDebugPanel(DebugPanel):
+    name = "Signals"
+    has_content = True
+
+    SIGNALS = {
+        'request_started': request_started,
+        'request_finished': request_finished,
+        'got_request_exception': got_request_exception,
+        'connection_created': connection_created,
+        'class_prepared': class_prepared,
+        'pre_init': pre_init,
+        'post_init': post_init,
+        'pre_save': pre_save,
+        'post_save': post_save,
+        'pre_delete': pre_delete,
+        'post_delete': post_delete,
+        'post_syncdb': post_syncdb,
+    }
+
+    def title(self):
+        return "Signals"
+
+    def url(self):
+        return ''
+
+    def signals(self):
+        signals = self.SIGNALS.copy()
+        if hasattr(settings, 'DEBUG_TOOLBAR_CONFIG'):
+            extra_signals = settings.DEBUG_TOOLBAR_CONFIG.get('EXTRA_SIGNALS', [])
+        else:
+            extra_signals = []
+        for signal in extra_signals:
+            parts = signal.split('.')
+            path = '.'.join(parts[:-1])
+            __import__(path)
+            signals[parts[-1]] = getattr(sys.modules[path], parts[-1])
+        return signals
+    signals = property(signals)
+
+    def content(self):
+        signals = []
+        keys = self.signals.keys()
+        keys.sort()
+        for name in keys:
+            signal = self.signals[name]
+            receivers = []
+            for (receiverkey, r_senderkey), receiver in signal.receivers:
+                if isinstance(receiver, WEAKREF_TYPES):
+                    receiver = receiver()
+                if receiver is None:
+                    continue
+                if getattr(receiver, 'im_self', None) is not None:
+                    text = "method %s on %s object" % (receiver.__name__, receiver.im_self.__class__.__name__)
+                elif getattr(receiver, 'im_class', None) is not None:
+                    text = "method %s on %s" % (receiver.__name__, receiver.im_class.__name__)
+                else:
+                    text = "function %s" % receiver.__name__
+                receivers.append(text)
+            signals.append((name, signal, receivers))
+        return render_to_string('debug_toolbar/panels/signals.html', {'signals': signals})