A reusable Django app for queueing the sending of email (forked of APSL/django-mailer-2, which is unmaintained)

## Project description

django-mailer-2 is asynchronous so in addition to putting mail on the queue you need to periodically tell it to clear the queue and actually send the mail.

The latter is done via a command extension.

## Putting Mail On The Queue (Django 1.2 or higher)

In settings.py, configure Django’s EMAIL_BACKEND setting like so:

EMAIL_BACKEND = ‘django_mailer.smtp_queue.EmailBackend’

If you don’t need message priority support you can call send_mail like you normally would in Django:

send_mail(subject, message_body, settings.DEFAULT_FROM_EMAIL, recipients)

If you need prioritized messages, create an instance of EmailMessage and specify {‘X-Mail-Queue-Priority’: ‘<value>’} in the headers parameter, where <value> is one of:

‘now’ - do not queue, send immediately ‘high’ - high priority ‘normal’ - standard priority - this is the default. ‘low’ - low priority

If you don’t specify a priority, the message is sent at ‘normal’ priority.

## Putting Mail On The Queue (Django 1.1 or earlier)

Because django-mailer currently uses the same function signature as Django’s core mail support you can do the following in your code:

# favour django-mailer-2 but fall back to django.core.mail
from django.conf import settings

if "django_mailer" in settings.INSTALLED_APPS:
from django_mailer import send_mail
else:
from django.core.mail import send_mail

and then just call send_mail like you normally would in Django:

send_mail(subject, message_body, settings.DEFAULT_FROM_EMAIL, recipients)

mail_admins(subject, message_body)

or all managers as defined in the MANAGERS setting by calling:

mail_managers(subject, message_body)

## Command Extensions

With mailer in your INSTALLED_APPS, there will be four new manage.py commands you can run:

• send_mail will clear the current message queue. If there are any failures, they will be marked deferred and will not be attempted again by send_mail.

• retry_deferred will move any deferred mail back into the normal queue (so it will be attempted again on the next send_mail).

• cleanup_mail will delete mails created before an X number of days (defaults to 90).

• status_mail the intent of this commant is to allow systems as nagios to

be able to ask the queue about its status. It returns as string with than can be parses as (?P<queued>\d+)/(?P<deferred>\d+)/(?P<seconds>\d+)

You may want to set these up via cron to run regularly:

* * * * * (cd $PROJECT; python manage.py send_mail >>$PROJECT/cron_mail.log 2>&1)
0,20,40 * * * * (cd $PROJECT; python manage.py retry_deferred >>$PROJECT/cron_mail_deferred.log 2>&1)
0 1 * * * (cd $PROJECT; python manage.py cleanup_mail --days=30 >>$PROJECT/cron_mail_cleanup.log 2>&1)

This attempts to send mail every minute with a retry on failure every 20 minutes and will run a cleanup task every day cleaning all the messaged created before 30 days.

manage.py send_mail uses a lock file in case clearing the queue takes longer than the interval between calling manage.py send_mail.

Note that if your project lives inside a virtualenv, you also have to execute this command from the virtualenv. The same, naturally, applies also if you’re executing it with cron.

## Project details

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