Jul 17 - Fill the gaps between Single-tenant mode and Multi-tenant mode - MT7

app/billing/emails.py

@@ -8,7 +8,6 @@ app/templates/billing/email/.
 
 import logging
 import threading
-from urllib.parse import urlparse
 from flask import current_app, render_template
 from flask_mail import Message
 from app import mail
@@ -92,10 +91,14 @@ def send_billing_email(to_addr: str, event_type: str, context_dict: dict):
 
     app = current_app._get_current_object()
 
-    # Derive noreply sender from APP_BASE_URL so billing emails match the tenant domain.
+    # Branded From: the display NAME tracks the tenant, the ADDRESS stays the
+    # authenticated identity unless the domain is DNS-authorized. Resolved HERE,
+    # in the request context, because _send() runs on a background thread where
+    # g.tenant no longer exists. The previous `noreply@{netloc}` sent from the
+    # tenant's host regardless of SPF authorization. See app/utils/mail_utils.py.
     try:
-        _netloc = urlparse(app.config.get('APP_BASE_URL', '')).netloc
-        _sender = f'noreply@{_netloc}' if _netloc else app.config.get('MAIL_DEFAULT_SENDER', '')
+        from app.utils.mail_utils import branded_sender
+        _sender = branded_sender(app.config.get('APP_BASE_URL', ''))
     except Exception:
         _sender = app.config.get('MAIL_DEFAULT_SENDER', '')