Django Email Testing

Django Email Testing

Idea: In tests, Django can use an in-memory backend so nothing is really sent. All “sent” emails go to mail.outbox (a list).

• Test settings: EMAIL_BACKEND = 'django.core.mail.backends.locmem.EmailBackend' (or leave default in tests; many setups use locmem). Then from django.core import mail and assert on mail.outbox.
• Assert: len(mail.outbox) == 1, mail.outbox[0].subject, mail.outbox[0].to, mail.outbox[0].body. For HTML: mail.outbox[0].alternatives.
• Views that send email: Call the view (e.g. post to register), then assert outbox. No sleep — with locmem it’s synchronous.
• Templates: Render with render_to_string('emails/welcome.html', context) and assert content, or send and assert body/alternatives.
• Celery tasks that send email: Use CELERY_ALWAYS_EAGER=True in tests so the task runs inline, then check mail.outbox. Or mock send_mail and assert it was called with the right args.

Avoid: time.sleep() to “wait” for email. Use the right backend and/or EAGER so everything is immediate.

Clear outbox between tests: mail.outbox is usually cleared per test; if not, mail.outbox.clear() in setUp.