> After my comment in the steering council vote and in-person conversation with Jake, I believe the SMTP backend will not be implemented for DEP 14
Then I can improve my earlier response: I *am confident* this proposal will have *no impact* on background workers. :-) - Mike On Tuesday, June 25, 2024 at 4:38:11 AM UTC-7 Adam Johnson wrote: > After my comment in the steering council vote and in-person conversation > with Jake, I believe the SMTP backend will not be implemented for DEP 14 : > https://forum.djangoproject.com/t/steering-council-vote-on-background-tasks-dep-14/31131/20 > > On Tue, 25 Jun 2024, at 10:27, Arthur Pemberton wrote: > > > The background workers proposal will implement a new background SMTP > EmailBackend (in django.core.mail.backends). > > I had missed that fact. Thanks for the explanation. > > I for one think that this is a good proposal -- this would modern > transactional email sending. > > - Arthur > > > On Mon, Jun 24, 2024 at 3:14 PM Mike Edmunds <medm...@gmail.com> wrote: > > > Would this be designed to be compatible with "Proposal 14: Background > Workers"? > > I wouldn't expect this to impact background workers one way or the other. > The same goes for the async email proposal(s) floating around. > > Virtually all of this work would occur in django.core.mail.message, where > Python's `email` APIs are used. A goal is to avoid changes that would break > existing email backends (Django or third-party). > > The background workers proposal will implement a new background SMTP > EmailBackend (in django.core.mail.backends). The existing SMTP EmailBackend > doesn't directly use Python's `email` APIs, and there should be no reason > for background SMTP to be any different. (It might be helpful to know that > Python's `email` library isn't involved in *sending* email; that's > handled by Python's `smtplib`, which Django uses only in the SMTP > EmailBackend.) > > The existing SMTP EmailBackend *does* use one function I expect will > become deprecated: django.core.mail.message.sanitize_address(). I haven't > yet investigated whether that use is still necessary, or whether it's there > to get around past bugs/limitations in Python's smtplib. If any of it is > still needed for SMTP, I'd probably want to move that code into the SMTP > EmailBackend(s). > > - Mike > On Sunday, June 23, 2024 at 10:22:03 PM UTC-7 Arthur Pemberton wrote: > > Would this be designed to be compatible with "Proposal 14: Background > Workers"? > > > > > On Sun, Jun 23, 2024 at 10:46 PM Mike Edmunds <medm...@gmail.com> wrote: > > I want to propose updating django.core.mail to replace use of Python's > legacy email.message.Message (and other legacy email APIs) with > email.message.EmailMessage (and other modern APIs). > > If there's interest, I can put together a more detailed proposal and/or > ticket, but was hoping to get some initial feedback first. (I searched for > relevant discussions in django-developers and the issue tracker, and didn't > find any. Apologies if this has come up before.) > > [Note: I maintain django-anymail > <https://github.com/anymail/django-anymail>, which implements Django > integration with several transactional email service providers.] > > > *Background* > > Since Python ~3.6, Python's email package has included two largely > separate implementations: > > - a "modern (unicode friendly) API" based on > email.message.EmailMessage and email.policy.default > - a "legacy API" providing compatibility with older Python versions, > based on email.message.Message and email.policy.compat32 > > (See https://docs.python.org/3/library/email.html, especially toward the > end.) > > django.core.mail currently uses the legacy API. > > > *Why switch?* > > There are no plans to deprecate Python's legacy email API, and it's > working, so why change Django? > > - > > *Fewer bugs:* The modern API fixes a *lot* of bugs in the legacy API. > My understanding is legacy bugs will generally not be fixed. (And in fact, > there are some cases where the legacy API deliberately replicates earlier > buggy behavior.) > > Django #35497 <https://code.djangoproject.com/ticket/35497> is an > example of a legacy bug (with a problematic proposed workaround) which is > just fixed in the modern API. > - > > *Simpler, safer code:* A substantial portion > > <https://github.com/django/django/blob/stable/5.1.x/django/core/mail/message.py#L32-L190> > of > django.core.mail's internals implements workarounds and security fixes for > problems in the legacy API. This would be greatly simplified—maybe > eliminated completely—using the modern API. > > Examples: the modern API prevents CR/NL injections in message headers. > It serializes and folds address headers properly—even ones with unicode > names. It enforces single-instance headers where appropriate. > - > > *Easier to work with:* The modern API adds some nice conveniences for > developers working in django.core.mail, third-party library developers, > and > (depending on what we choose to expose) users of Django's mail APIs. > > Examples: populating the "Date" header with a datetime or an address > header with Address > > <https://docs.python.org/3/library/email.headerregistry.html#email.headerregistry.Address> > objects—without > needing intricate knowledge of email header formats. Using email.policy to > generate a 7-bit clean serialization (without having to muck about > with the MIME parts > > <https://github.com/anymail/django-anymail/blob/v11.0/anymail/backends/amazon_ses.py#L168-L179> > ). > > > *Concerns & risks* > > Compatibility and security, of course… > > - > > *Backwards compatibility (for API users):* django.core.mail largely > insulates callers from the underlying Python email package. There are a > few > places where this leaks (e.g., attachments > > <https://docs.djangoproject.com/en/5.0/topics/email/#django.core.mail.EmailMessage:~:text=send()%20is%20called.-,attachments,-%3A%20A%20list%20of> > allows > legacy email MIMEBase > <https://docs.python.org/3/library/email.mime.html> objects), but in > general the switch should be transparent. (And I have some ideas for > supporting the other cases.) > - > > *Backwards compatibility (for third-party libraries):* Some libraries > may use internals I'd propose removing (e.g., SafeMIME and friends); > we'd handle this through deprecation. > - > > *Backwards compatibility (bug-level):* There's probably some code out > there that unintentionally depends on legacy email bugs (or the specific > ways Django works around them). I don't have any examples, but I also > don't > have a good solution for when they surface. Plus, while Python's modern > email API is pretty mature at this point, there are still new bugs being > reported against it. Email is complicated. > - > > *Security:* As noted above, the modern API should be more secure than > the legacy one. But we also have a nice collection of email security > tests—which *mostly* don't depend on internal implementation. We'd > keep these. > > > -- > > You received this message because you are subscribed to the Google Groups > "Django developers (Contributions to Django itself)" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to django-develop...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-developers/f410ad79-a034-4275-88a7-22e7626c06fdn%40googlegroups.com > > <https://groups.google.com/d/msgid/django-developers/f410ad79-a034-4275-88a7-22e7626c06fdn%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > > -- > You received this message because you are subscribed to the Google Groups > "Django developers (Contributions to Django itself)" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to django-develop...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-developers/8f4716b9-0856-46bd-af16-0ce715f195b2n%40googlegroups.com > > <https://groups.google.com/d/msgid/django-developers/8f4716b9-0856-46bd-af16-0ce715f195b2n%40googlegroups.com?utm_medium=email&utm_source=footer> > . > > > -- > You received this message because you are subscribed to the Google Groups > "Django developers (Contributions to Django itself)" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to django-develop...@googlegroups.com. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/django-developers/CA%2BX4dQSCwndDFcOid0Lyi4PtUJw264DTZK-r6vSNNoRh%2B4gBTQ%40mail.gmail.com > > <https://groups.google.com/d/msgid/django-developers/CA%2BX4dQSCwndDFcOid0Lyi4PtUJw264DTZK-r6vSNNoRh%2B4gBTQ%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > > -- You received this message because you are subscribed to the Google Groups "Django developers (Contributions to Django itself)" group. 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