Optmize email normalization

kitsune/sumo/email_utils.py

@@ -13,7 +13,6 @@
 from post_office.settings import get_override_recipients
 from premailer import transform
 
-
 log = logging.getLogger("k.email")
 
 
@@ -31,34 +30,28 @@ def normalize_gmail(email: str) -> str:
     return email
 
 
-def is_valid_email(email: str) -> bool:
-    """
-    Returns True if the given email address is valid, False otherwise.
-    """
-    try:
-        validate_email(normalize_gmail(email))
-    except ValidationError:
-        return False
-    return True
-
-
 def send_messages(messages):
     """Sends a bunch of email messages."""
     if not messages:
         return
 
-    # Only send each message to its valid recipients,
-    # excluding messages without any valid recipients.
-    cleaned_messages = []
+    valid_messages = []
     for message in messages:
-        # Remove invalid emails and normalize gmails.
-        cleaned_to = [normalize_gmail(email) for email in message.to if is_valid_email(email)]
-        if cleaned_to:
-            message.to = cleaned_to
-            cleaned_messages.append(message)
+        valid_emails = []
+        for email in message.to:
+            normalized_email = normalize_gmail(email)
+            try:
+                validate_email(normalized_email)
+                valid_emails.append(normalized_email)
+            except ValidationError:
+                pass
+
+        if valid_emails:
+            message.to = valid_emails
+            valid_messages.append(message)
 
     with mail.get_connection(fail_silently=True) as conn:
-        conn.send_messages(cleaned_messages)
+        conn.send_messages(valid_messages)
 
 
 def safe_translation(f):

kitsune/sumo/tests/test_email_utils.py

@@ -3,8 +3,8 @@
 from django.conf import settings
 from django.contrib.sites.models import Site
 from django.core.mail import EmailMultiAlternatives
-from django.utils.functional import lazy
 from django.utils import translation
+from django.utils.functional import lazy
 from django.utils.translation import get_language
 
 from kitsune.sumo.email_utils import emails_with_users_and_watches, safe_translation, send_messages
@@ -156,3 +156,20 @@ def test_send_messages(self, mock_mail):
         self.assertEqual(messages[1].to, ["georgeharrison@gmail.com"])
         self.assertEqual(messages[2].to, ["paulmccartney@gmail.com"])
         self.assertEqual(messages[3].to, ["ringo@beatles.com", "george@beatles.com"])
+
+    @patch("kitsune.sumo.email_utils.mail")
+    def test_send_messages_with_invalid_email(self, mock_mail):
+        from_email = "notifications@support.mozilla.org"
+        messages = [
+            EmailMultiAlternatives(
+                "Test",
+                "Testing",
+                from_email,
+                ["valid@example.com", "invalid@email", "another.valid@example.com"],
+            ),
+        ]
+        send_messages(messages)
+        send_messages_mock = mock_mail.get_connection().__enter__().send_messages
+        send_messages_mock.assert_called_once_with(messages)
+        # Check that the invalid email was removed
+        self.assertEqual(messages[0].to, ["valid@example.com", "another.valid@example.com"])