django-mailer

Django-mailer is a powerful asynchronous tool for managing email tasks. It allows you to add your email to the queue and send it later. To ensure that your emails are sent on time, you need to periodically clear the queue through a command extension.

Here are some sample use cases for Django-mailer:
- Sending one-off announcements to all users on a site
- Sending emails to specific subsets of users
- Scheduling emails to be sent at a particular date or time
- Sending regular emails to a subset of users
- Notifying users of events relevant to them
- Creating email digests for users who don't want individual notifications

It's important to note that Django-mailer shouldn't manage subscriptions to events. For instance, if a user subscribes to a message board thread, the overall site should keep track of this information. Django-mailer would simply be asked to send the same message to that list of users.

Putting email on the queue is easy with Django-mailer. If you prefer to use it, simply fall back to Django's core mail support. You can call send_mail like you usually would in Django. Additionally, you can use mail_admins and mail_managers to send emails to all admins or managers.

To clear the queue and send emails, Django-mailer comes with two new manage.py commands: send_mail and retry_deferred. You can run these commands regularly via cron to ensure that emails are sent on time. Manage.py send_mail even comes with a lock file to prevent queue clearing from taking too long.

Overall, Django-mailer is an excellent tool for managing email tasks in Django. Despite its asynchronous nature, it's easy to set up and use, making it a popular choice amongst developers.