Do not send newsletter if failed to render template

plexpy/newsletters.py

@@ -288,9 +288,9 @@ def serve_template(templatename, **kwargs):
 
     try:
         template = _hplookup.get_template(templatename)
-        return template.render(**kwargs)
+        return template.render(**kwargs), False
     except:
-        return exceptions.html_error_template().render()
+        return exceptions.html_error_template().render(), True
 
 
 def generate_newsletter_uuid():
@@ -376,6 +376,7 @@ class Newsletter(object):
         self.newsletter = None
 
         self.is_preview = False
+        self.template_error = None
 
     def set_config(self, config=None, default=None):
         return self._validate_config(config=config, default=default)
@@ -421,7 +422,7 @@ class Newsletter(object):
 
         self.retrieve_data()
 
-        newsletter_rendered = serve_template(
+        newsletter_rendered, self.template_error = serve_template(
             templatename=self._TEMPLATE,
             uuid=self.uuid,
             subject=self.subject_formatted,
@@ -432,6 +433,9 @@ class Newsletter(object):
             preview=self.is_preview
         )
 
+        if self.template_error:
+            return newsletter_rendered
+
         # Force Tautulli footer
         if '<!-- FOOTER MESSAGE - DO NOT REMOVE -->' in newsletter_rendered:
             newsletter_rendered = newsletter_rendered.replace(
@@ -439,7 +443,7 @@ class Newsletter(object):
                 'Newsletter generated by <a href="https://tautulli.com" target="_blank" '
                 'style="text-decoration: underline;color: inherit;font-size: inherit;">Tautulli</a>.'
             )
-            return newsletter_rendered
+
         else:
             msg = ('<div style="text-align: center;padding-top: 100px;padding-bottom: 100px;">'
                    '<p style="font-family: \'Open Sans\', Helvetica, Arial, sans-serif;color: #282A2D;'
@@ -449,11 +453,16 @@ class Newsletter(object):
                    '<a href="https://tautulli.com" target="_blank">Tautulli</a>.<br>Thank you.'
                    '</p></div>')
             newsletter_rendered = re.sub(r'(<body.*?>)', r'\1' + msg, newsletter_rendered)
+
         return newsletter_rendered
 
     def send(self):
         self.newsletter = self.generate_newsletter()
 
+        if self.template_error:
+            logger.error(u"Tautulli Newsletters :: %s newsletter failed to render template. Newsletter not sent." % self.NAME)
+            return False
+
         if not self._has_data():
             logger.warn(u"Tautulli Newsletters :: %s newsletter has no data. Newsletter not sent." % self.NAME)
             return False