stages/email: fix sending emails from task (#7325)

closes #7322

Signed-off-by: Jens Langhammer <jens@goauthentik.io>

authentik/stages/email/tasks.py

@@ -13,6 +13,7 @@ from authentik.events.models import Event, EventAction
 from authentik.events.monitored_tasks import MonitoredTask, TaskResult, TaskResultStatus
 from authentik.root.celery import CELERY_APP
 from authentik.stages.email.models import EmailStage
+from authentik.stages.email.utils import logo_data
 
 LOGGER = get_logger()
 
@@ -81,6 +82,10 @@ def send_mail(self: MonitoredTask, message: dict[Any, Any], email_stage_pk: Opti
         # Because we use the Message-ID as UID for the task, manually assign it
         message_object.extra_headers["Message-ID"] = message_id
 
+        # Add the logo (we can't add it in the previous message since MIMEImage
+        # can't be converted to json)
+        message_object.attach(logo_data())
+
         LOGGER.debug("Sending mail", to=message_object.to)
         backend.send_messages([message_object])
         Event.new(

authentik/stages/email/utils.py

@@ -9,7 +9,7 @@ from django.utils import translation
 
 
 @lru_cache()
-def logo_data():
+def logo_data() -> MIMEImage:
     """Get logo as MIME Image for emails"""
     path = Path("web/icons/icon_left_brand.png")
     if not path.exists():
@@ -29,5 +29,4 @@ class TemplateEmailMessage(EmailMultiAlternatives):
         super().__init__(**kwargs)
         self.content_subtype = "html"
         self.mixed_subtype = "related"
-        self.attach(logo_data())
         self.attach_alternative(html_content, "text/html")