From 80813addb9b588682ba1d5d52b35157a8859e61f Mon Sep 17 00:00:00 2001
From: Serghei Mihai <smihai@entrouvert.com>
Date: Tue, 4 Oct 2016 17:03:28 +0200
Subject: [PATCH] compute email message body once (#13552)

---
 corbo/models.py                     | 26 ++++++++++++++------------
 corbo/templates/corbo/announce.html |  2 +-
 2 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/corbo/models.py b/corbo/models.py
index 03617fb..f78fba6 100644
--- a/corbo/models.py
+++ b/corbo/models.py
@@ -24,6 +24,8 @@ channel_choices = (
     ('homepage', _('Homepage'))
 )
 
+UNSUBSCRIBE_LINK_PLACEHOLDER = '##UNSUBSCRIBE_LINK_PLACEHOLDER##'
+
 logger = logging.getLogger(__name__)
 
 
@@ -113,7 +115,15 @@ class Broadcast(models.Model):
         total_sent = 0
         handler = HTML2Text()
         template = loader.get_template('corbo/announce.html')
-        m = Message(subject=self.announce.title, mail_from=settings.CORBO_DEFAULT_FROM_EMAIL)
+        message = Message(subject=self.announce.title, mail_from=settings.CORBO_DEFAULT_FROM_EMAIL,
+                    html=template.render(Context({'content': self.announce.text,
+                                                  'unsubscribe_link_placeholder': UNSUBSCRIBE_LINK_PLACEHOLDER})))
+        message.transformer.apply_to_images(func=transform_image_src)
+        # perform transformations in message html, like inline css parsing
+        message.transformer.load_and_transform()
+        # mark all attached images as inline
+        message.transformer.make_all_images_inline()
+        message.transformer.save()
         for s in subscriptions:
             if not s.identifier:
                 continue
@@ -121,18 +131,10 @@ class Broadcast(models.Model):
                                                'identifier': s.identifier})
             unsubscribe_link = urlparse.urljoin(settings.SITE_BASE_URL, reverse('unsubscribe',
                                     kwargs={'unsubscription_token': unsubscribe_token}))
-            message = template.render(Context({'unsubscribe_link': unsubscribe_link,
-                                               'content': self.announce.text}))
-            m.html = message
-            m.transformer.apply_to_images(func=transform_image_src)
-            # perform transformations in message html, like inline css parsing
-            m.transformer.load_and_transform()
-            # mark all attached images as inline
-            m.transformer.make_all_images_inline()
-            m.transformer.save()
+            message.html = message.html.replace(UNSUBSCRIBE_LINK_PLACEHOLDER, unsubscribe_link)
             handler.body_width = 0
-            m.text = handler.handle(m.html)
-            sent = m.send(to=s.identifier)
+            message.text = handler.handle(message.html)
+            sent = message.send(to=s.identifier)
             if sent:
                 total_sent += 1
                 logger.info('Announce "%s" sent to %s', self.announce.title, s.identifier)
diff --git a/corbo/templates/corbo/announce.html b/corbo/templates/corbo/announce.html
index 39592e4..ae6a6e2 100644
--- a/corbo/templates/corbo/announce.html
+++ b/corbo/templates/corbo/announce.html
@@ -4,6 +4,6 @@
 </div>
 <div class="footer">
   {% blocktrans %}
-  Click <a href='{{ unsubscribe_link}}'>here</a> to unsubscribe from this newsletter.
+  Click <a href='{{ unsubscribe_link_placeholder }}'>here</a> to unsubscribe from this newsletter.
   {% endblocktrans %}
 </div>
-- 
2.9.3