From f84e202ade81aabe2fd85bd60eecba3b26898f01 Mon Sep 17 00:00:00 2001
From: Anthony Monthe <anthony.monthe@gmail.com>
Date: Mon, 22 Feb 2021 02:13:37 +0000
Subject: [PATCH] Added Signals

---
 newsletter/models.py  | 18 +++++++++-----
 newsletter/signals.py |  8 +++++++
 tests/test_mailing.py | 55 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 75 insertions(+), 6 deletions(-)
 create mode 100644 newsletter/signals.py

diff --git a/newsletter/models.py b/newsletter/models.py
index 65331fed..9267d763 100644
--- a/newsletter/models.py
+++ b/newsletter/models.py
@@ -19,6 +19,7 @@
 
 from distutils.version import LooseVersion
 
+from . import signals
 from .fields import DynamicImageField
 from .utils import (
     make_activation_code, get_default_sites, ACTIONS
@@ -584,6 +585,7 @@ def submit(self):
         assert self.publish_date < now(), \
             'Something smells fishy; submission time in future.'
 
+        signals.pre_submit.send(sender=self.__class__, message=self)
         self.sending = True
         self.save()
 
@@ -600,6 +602,7 @@ def submit(self):
         finally:
             self.sending = False
             self.save()
+            signals.post_submit.send(sender=self.__class__, message=self)
 
     def send_message(self, subscription):
         variable_dict = {
@@ -635,14 +638,14 @@ def send_message(self, subscription):
                 "text/html"
             )
 
+        signals.pre_send.send(sender=self.__class__, message=self, email=message)
+        logger.debug(
+            gettext('Submitting message to: %s.'),
+            subscription
+        )
+        error = None
         try:
-            logger.debug(
-                gettext('Submitting message to: %s.'),
-                subscription
-            )
-
             message.send()
-
         except Exception as e:
             # TODO: Test coverage for this branch.
             logger.error(
@@ -651,6 +654,9 @@ def send_message(self, subscription):
                 {'subscription': subscription,
                  'error': e}
             )
+            error = e
+        signals.post_send.send(sender=self.__class__, message=self, email=message,
+                               error=error)
 
     @classmethod
     def submit_queue(cls):
diff --git a/newsletter/signals.py b/newsletter/signals.py
new file mode 100644
index 00000000..adab7e8f
--- /dev/null
+++ b/newsletter/signals.py
@@ -0,0 +1,8 @@
+import django.dispatch
+
+
+pre_submit = django.dispatch.Signal()
+post_submit = django.dispatch.Signal()
+
+pre_send = django.dispatch.Signal()
+post_send = django.dispatch.Signal()
diff --git a/tests/test_mailing.py b/tests/test_mailing.py
index 267cda8b..e936f74b 100644
--- a/tests/test_mailing.py
+++ b/tests/test_mailing.py
@@ -16,6 +16,7 @@
 )
 from newsletter.utils import ACTIONS
 
+from newsletter import signals
 from .utils import MailTestCase, UserTestCase, template_exists
 
 NUM_SUBSCRIBED = 2
@@ -490,3 +491,57 @@ def assertSentEmailIsProper(self, action):
         self.assertEmailAlternativeBodyContains(
             'override for %s.html' % action
         )
+
+
+class SubmitSignalTestCase(MailingTestCase):
+    def test_pre_submit(self):
+        self.called = False
+        def handler(sender, message, **kwargs):
+            self.called = True
+        signals.pre_submit.connect(handler, dispatch_uid='test-pre-submit')
+        sub = Submission.from_message(self.m)
+        sub.submit()
+        self.assertTrue(self.called)
+        signals.post_send.disconnect(dispatch_uid='test-pre-submit')
+
+    def test_post_submit(self):
+        self.called = False
+        def handler(sender, message, **kwargs):
+            self.called = True
+        signals.post_submit.connect(handler, dispatch_uid='test-post-submit')
+        sub = Submission.from_message(self.m)
+        sub.submit()
+        self.assertTrue(self.called)
+        signals.post_send.disconnect(dispatch_uid='test-post-submit')
+
+    def test_pre_send(self):
+        self.called = 0
+        def handler(sender, message, **kwargs):
+            self.called += 1
+        signals.pre_send.connect(handler, dispatch_uid='test-pre-send')
+        sub = Submission.from_message(self.m)
+        sub.submit()
+        self.assertEqual(self.called, 2)
+        signals.post_send.disconnect(dispatch_uid='test-pre-send')
+
+    def test_post_send(self):
+        self.called = 0
+        def handler(sender, message, **kwargs):
+            self.called += 1
+        signals.post_send.connect(handler, dispatch_uid='test-post-send')
+        sub = Submission.from_message(self.m)
+        sub.submit()
+        self.assertEqual(self.called, 2)
+        signals.post_send.disconnect(dispatch_uid='test-post-send')
+
+    @mock.patch('django.core.mail.EmailMultiAlternatives.send', side_effect=Exception())
+    def test_post_send_failed(self, mock_send):
+        self.called = 0
+        def handler(sender, message, error, **kwargs):
+            self.assertIsNotNone(error)
+            self.called += 1
+        signals.post_send.connect(handler, dispatch_uid='test-post-send')
+        sub = Submission.from_message(self.m)
+        sub.submit()
+        self.assertEqual(self.called, 2)
+        signals.post_send.disconnect(dispatch_uid='test-post-send')