- Changed EmailMessage.message() to construct a "modern email API"
email.message.EmailMessage and added policy keyword arg.
- Added support for modern MIMEPart objects in EmailMessage.attach()
(and EmailMessage constructor, EmailMessage.attachments list).
- Updated SMTP EmailBackend to use modern email.policy.SMTP.
Deprecated:
- Attaching MIMEBase objects (replace with MIMEPart)
- BadHeaderError (modern email uses ValueError)
- SafeMIMEText, SafeMIMEMultipart (unnecessary for modern email)
- django.core.mail.forbid_multi_line_headers()
(undocumented, but exposed via `__all__` and in wide use)
- django.core.mail.message.sanitize_address()
(undocumented, but in wide use)
Removed without deprecation (all undocumented):
- EmailMessage.mixed_subtype
- EmailMultiAlternatives.alternative_subtype
- Support for setting (undocumented) EmailMessage.encoding property
to a legacy email.charset.Charset object
Related changes:
- Dropped tests for incorrect RFC 2047 encoding of non-ASCII email
address localparts. This is specifically prohibited by RFC 2047, and
not supported by any known MTA or email client. (Python still
mis-applies encoded-word to non-ASCII localparts, but it is a bug that
may be fixed in the future.)
- Added tests that try to discourage using Python's legacy email APIs
in future updates to django.core.mail.