Enqueue and send¶
Putting emails in the queue¶
Yubin replaces the standard Django Email Backend with its own. Instead of sending emails synchronously trough a SMTP server, Yubin saves and equeues emails in your database and creates Celery tasks to send them asynchronously using “the real” Django Email Backend.
# settings.py
# Yubin email backend that enqueue emails
EMAIL_BACKEND = 'django_yubin.backends.QueuedEmailBackend'
# "The real" email backend for sending emails
MAILER_USE_BACKEND = 'django.core.mail.backends.smtp.EmailBackend'
Now, you can call send_mail like you normally do in Django or using
mail views
send_mail(subject, message_body, settings.DEFAULT_FROM_EMAIL, recipients)
# ...
WelcomeMessageView(user).send()
Tasks¶
Once you have your emails queued in the database, you can send, retry or delete them using the following Celery tasks:
send_email(message_pk) Sends the email from the database with the given primay key.
retry_emails(max_retries=3) Retry sending retryable emails (failed, blacklisted or discarded) enqueueing them again.
delete_old_emails(days=90) Delete emails created before days days.
You don’t usually need to create a send_email task, Yubin email backend does it automatically. For retry_emails and delete_old_emails, you can use Celery Beat to schedule periodic task.
Remember to have at least one Celery worker listening for tasks.
Commands¶
In addition to tasks, Yubin also provides a couple of commands to facilitate the development:
send_test_mail Sends a single HTML email. Ideal for checking connection parameters.
create_email Creates fake mails for testing unicode, emojis and attachments.
db2file and file2db migrate emails between storage backends. Look at the Storage backends section for more details.
Execute python manage.py THE_COMMAND --help to see optional arguments.
Health check¶
If you have added url(r'^yubin/', include('django_yubin.urls')) to your urls.py, you can go
to http://localhost:8000/yubin/health and see the health output result.
Response when there are no problems: HTTP 200
oldest_queued_email: 1 mins
emails_queued_too_old: no
threshold: 30 mins
Response if there are emails that have been too long enqueued: HTTP 500
# HTTP 500
oldest_queued_email: 45 mins
emails_queued_too_old: yes
threshold: 30 mins
You can parse this view’s response in your check system and check the status code of the response.
Additionally, you can use a different threshold changing settings.MAILER_HC_QUEUED_LIMIT_OLD or
passing a GET parameter t: http://localhost:8000/yubin/health?t=60