models: Move signal to 'signals'

Additional signals are going to be added shortly and they shouldn't
pollute 'models.py'.

Signed-off-by: Stephen Finucane <stephen@that.guru>
Tested-by: Daniel Axtens <dja@axtens.net>

1 files changed, 63 insertions, 0 deletions

diff --git a/patchwork/signals.py b/patchwork/signals.py
new file mode 100644
index 0000000..6f7f5ea
--- /dev/null
+++ b/patchwork/signals.py
@@ -0,0 +1,63 @@
+# Patchwork - automated patch tracking system
+# Copyright (C) 2016 Stephen Finucane <stephen@that.guru>
+#
+# This file is part of the Patchwork package.
+#
+# Patchwork is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# Patchwork is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Patchwork; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+from datetime import datetime as dt
+
+from django.db.models.signals import pre_save
+from django.dispatch import receiver
+
+from patchwork.models import Patch
+from patchwork.models import PatchChangeNotification
+
+
+@receiver(pre_save, sender=Patch)
+def patch_change_callback(sender, instance, **kwargs):
+    # we only want notification of modified patches
+    if instance.pk is None:
+        return
+
+    if instance.project is None or not instance.project.send_notifications:
+        return
+
+    try:
+        orig_patch = Patch.objects.get(pk=instance.pk)
+    except Patch.DoesNotExist:
+        return
+
+    # If there's no interesting changes, abort without creating the
+    # notification
+    if orig_patch.state == instance.state:
+        return
+
+    notification = None
+    try:
+        notification = PatchChangeNotification.objects.get(patch=instance)
+    except PatchChangeNotification.DoesNotExist:
+        pass
+
+    if notification is None:
+        notification = PatchChangeNotification(patch=instance,
+                                               orig_state=orig_patch.state)
+    elif notification.orig_state == instance.state:
+        # If we're back at the original state, there is no need to notify
+        notification.delete()
+        return
+
+    notification.last_modified = dt.now()
+    notification.save()