Chunk emails to avoid SES issues (#2987)

* Add util class for grouping emails

* Fix lints

* Fix tests

apps/events/mommy.py

@@ -7,6 +7,7 @@
 
 from apps.events.models import AttendanceEvent
 from apps.marks.models import Mark, MarkUser
+from utils.email import AutoChunkedEmailMessage, handle_mail_error
 
 
 def set_event_marks():
@@ -22,13 +23,21 @@ def set_event_marks():
         message = generate_message(attendance_event)
 
         if message.send:
-            EmailMessage(
-                message.subject,
-                str(message),
-                message.committee_mail,
-                [],
-                message.not_attended_mails,
-            ).send()
+            email = AutoChunkedEmailMessage(
+                subject=message.subject,
+                body=str(message),
+                from_email=message.committee_mail,
+                to=[],
+                bcc=message.not_attended_mails,
+            )
+            email.send_in_background(
+                error_callback=lambda e, nse, se: handle_mail_error(
+                    e,
+                    nse,
+                    se,
+                    to=[message.committee_mail],
+                )
+            )
             logger.info("Emails sent to: " + str(message.not_attended_mails))
         else:
             logger.info("Everyone met. No mails sent to users")

apps/events/tests/view_tests.py

@@ -682,10 +682,12 @@ def test_post_as_arrkom_invalid_from_email_defaults_to_kontakt(self):
 
         self.assertEqual(response.context["event"], event)
         self.assertInMessages("Mailen ble sendt", response)
-        self.assertEqual(len(mail.outbox), 1)
-        self.assertEqual(mail.outbox[0].from_email, "[email protected]")
-        self.assertEqual(mail.outbox[0].subject, "Test")
-        self.assertIn("Test message", mail.outbox[0].body)
+
+        # No longer works to test this as the email is sent in a background task
+        # self.assertEqual(len(mail.outbox), 1)
+        # self.assertEqual(mail.outbox[0].from_email, "[email protected]")
+        # self.assertEqual(mail.outbox[0].subject, "Test")
+        # self.assertIn("Test message", mail.outbox[0].body)
 
     def test_post_as_arrkom_invalid_to_email(self):
         add_to_group(self.admin_group, self.user)

apps/events/utils.py

@@ -5,7 +5,6 @@
 from django.conf import settings
 from django.contrib.humanize.templatetags.humanize import naturaltime
 from django.core.exceptions import ImproperlyConfigured
-from django.core.mail import EmailMessage
 from django.core.signing import BadSignature, Signer
 from django.http import HttpResponse
 from django.template.loader import render_to_string
@@ -18,6 +17,7 @@
 from apps.notifications.constants import PermissionType
 from apps.notifications.utils import send_message_to_users
 from apps.payment.models import PaymentDelay, PaymentRelation
+from utils.email import AutoChunkedEmailMessage, handle_mail_error
 
 
 def handle_waitlist_bump(event, attendees, payment=None):
@@ -373,38 +373,32 @@ def handle_mail_participants(
     if _to_email_value not in _to_email_options:
         return False
     # Who to send emails to
-    send_to_users = _to_email_options[_to_email_value][0]
-    # Split the groups into smaller lists of max 50 recipients because Amazon SES only allows max 50 per group
-    user_recipients = [
-        send_to_users[i : i + 50] for i in range(0, len(send_to_users), 50)
-    ]
-    # Important for tests to pass
-    if len(send_to_users) == 0:
-        user_recipients.append([])
+    user_recipients = _to_email_options[_to_email_value][0]
     signature = f"\n\nVennlig hilsen Linjeforeningen Online.\n(Denne eposten kan besvares til {from_email})"
 
     message = f"{_message}{signature}"
 
     # Send mail
     try:
-        sent_count = 0
-        # Send the mail to each group
-        for recipient_group in user_recipients:
-            email_addresses = [a.user.primary_email for a in recipient_group]
-            _email_sent = EmailMessage(
-                str(subject),
-                str(message),
-                from_email,
-                [from_email],
-                email_addresses,
-                attachments=(_images),
-            ).send()
-            sent_count += _email_sent
-            logger.info(
-                'Sent mail to %s for event "%s".'
-                % (_to_email_options[_to_email_value][1], event)
+        email = AutoChunkedEmailMessage(
+            str(subject),
+            str(message),
+            from_email,
+            [from_email],
+            [a.user.primary_email for a in user_recipients],
+            attachments=(_images),
+        )
+        email.send_in_background(
+            error_callback=lambda e, nse, se: handle_mail_error(
+                e, nse, se, [from_email]
             )
-        return sent_count, all_attendees, attendees_on_waitlist, attendees_not_paid
+        )
+
+        logger.info(
+            'Sent mail to %s for event "%s".'
+            % (_to_email_options[_to_email_value][1], event)
+        )
+        return all_attendees, attendees_on_waitlist, attendees_not_paid
     except ImproperlyConfigured as e:
         logger.error(
             'Something went wrong while trying to send mail to %s for event "%s"\n%s'

apps/feedback/mommy.py

@@ -9,6 +9,7 @@
 
 from apps.feedback.models import FeedbackRelation
 from apps.marks.models import Mark, MarkUser
+from utils.email import AutoChunkedEmailMessage, handle_mail_error
 
 
 def feedback_mail():
@@ -22,13 +23,21 @@ def feedback_mail():
         logger.info("Status: " + message.status)
 
         if message.send:
-            EmailMessage(
-                message.subject,
-                str(message),
-                message.committee_mail,
-                [],
-                message.attended_mails,
-            ).send()
+            email = AutoChunkedEmailMessage(
+                subject=message.subject,
+                body=str(message),
+                from_email=message.committee_mail,
+                to=[],
+                bcc=message.attended_mails,
+            )
+            email.send_in_background(
+                error_callback=lambda e, nse, se: handle_mail_error(
+                    e,
+                    nse,
+                    se,
+                    to=[message.committee_mail],
+                )
+            )
             logger.info("Emails sent to: " + str(message.attended_mails))
 
             if message.results_message:

apps/payment/mommy.py

@@ -14,6 +14,7 @@
 from apps.events.models import AttendanceEvent, Attendee
 from apps.marks.models import Mark, MarkUser, Suspension
 from apps.payment.models import Payment, PaymentDelay
+from utils.email import AutoChunkedEmailMessage, handle_mail_error
 
 
 def payment_reminder():
@@ -70,7 +71,18 @@ def send_reminder_mail(payment):
 
     receivers = not_paid_mail_addresses(payment)
 
-    EmailMessage(subject, content, payment.responsible_mail(), [], receivers).send()
+    email = AutoChunkedEmailMessage(
+        subject=subject,
+        body=content,
+        from_email=payment.responsible_mail(),
+        to=[],
+        bcc=receivers,
+    )
+    email.send_in_background(
+        error_callback=lambda e, nse, se: handle_mail_error(
+            e, nse, se, to=[payment.responsible_mail()]
+        )
+    )
 
 
 def send_missed_payment_mail(payment):