Django overrides the default email charset behaviour for utf-8

[Simon Blanchard]

# Don't BASE64-encode UTF-8 messages so that we avoid unwanted attention from
# some spam filters.
Charset.add_charset('utf-8', Charset.SHORTEST, Charset.QP, 'utf-8')

The above bit of code in django.core.mail overrides the standard Python behaviour for utf-8 in the Python email module. It would be better to set the charset by calling set_charset() on the Message before sending if needed rather than a global override. This behaviour and assumption is not documented anywhere in Django as far as I can tell. I think this is a case of the framework being a bit too clever. Not everyone using Django is using the django email sending methods nor wants Django to (silently) change the system defaults.

For example, I use the standard Python email sending methods and was expecting the Python lib to behave as advertised but the encoding of my utf-8 messages kept coming out quoted-printable because of the override above.

[Aymeric Augustin]

Change UI/UX from NULL to False.

[Aymeric Augustin]

Change Easy pickings from NULL to False.

[Aymeric Augustin]

This also caused me a lot of trouble when I was writing a patch for #18916.

[Claude Paroz]

Do not change python global CHARSETS

[Claude Paroz]

Patch attached. Tests changes are only the different order of headers, nothing significant.

[anonymous]

Tests pass. I made a PR to make it easier to merge into master. ​https://github.com/django/django/pull/1376/files

[Preston Holmes]

Unfortunately the email tests have multiple failures under Python3 with this patch applied - I did not investigate the causes.

[Ramiro Morales]

Actually, the proposed patch tests fail with Python 3.3. They pass for 3.2.x (and 2.7..x).

The pre-3.3.0 Python commit where things break is:

changeset:   75893:9ceac471bd8c
user:        R David Murray <rdmurray@bitdance.com>
date:        Thu Mar 22 22:40:44 2012 -0400
summary:     #14380: Make actual default match docs, fix __init__ order.

See:

• ​http://bugs.python.org/issue14380
• ​http://hg.python.org/cpython/rev/9ceac471bd8c

Thank you very much to all individuals that have worked on this so far. I have a fix ready for review, will open a PR soon and post a link here so you can review it.

[Ramiro Morales]

This is the PR: ​https://github.com/django/django/pull/1489

[Ramiro Morales <cramm0@…>]

In ececbe77ff573707d8f25084018e66ee07f820fd:

Fixed #12422 -- Don't override global email charset behavior for utf-8.

Thanks simonb for the report, Claude Paroz and Susan Tan for their work
on a fix.

[Andrew Godwin <andrew@…>]

In 8e571e5f8f21d87ab5a5462730289c755b8022d3:

Fixed #12422 -- Don't override global email charset behavior for utf-8.

Thanks simonb for the report, Claude Paroz and Susan Tan for their work
on a fix.