Notification mail header "Precedence" should be configurable

[i.bardarov@…]

I want to use Trac to notify a mailing list of ticket change.

Every time when Trac send email I got this error/success in the mail log:

delivery 1118: success: Precedence:_junk_-_message_ignored/did_0+0+1/

To bypass this we have to comment in notification.py

headers['Precedence'] = 'bulk'

It should be great if you can include this as a config option in feature version.

Thanks

[anonymous]

#7499

[anonymous]

1. abc

1. def

1. 233

[Remy Blank]

An improved notification system is scheduled for 0.13.

[Emmanuel Blot]

#8609 flagged as duplicate

[Christian Boos]

(#8609 has a patch)

[Emmanuel Blot]

Replying to cboos:

(#8609 has a patch)

Note that disabling this header is a bad workaround that may lead to other issues, such as the ones for which these headers have been initially introduced. I'm not sure Trac should send 'limited' emails to circumvent issues in other software…

[dandre@…]

I have tested replacing

headers['Precedence'] = 'bulk'

with

headers['Precedence'] = 'list'

and the mail is correctly delivered. So instead of my previous patch in #8609 I suggest to set precedence header to list.

I suggest to change milestone from 0.13 to 0.11.6 too

[Thijs Triemstra]

+1 for making this configurable.

[Thijs Triemstra]

Replying to dandre@…:

I have tested replacing

headers['Precedence'] = 'bulk'

with

headers['Precedence'] = 'list'

Patch for 0.12-stable:

trac/notification.py

@@ -409 +409 @@
         headers['X-Trac-Version'] =  __version__
         headers['X-Trac-Project'] =  projname
         headers['X-URL'] = self.env.project_url
-        headers['Precedence'] = 'bulk'
+        headers['Precedence'] = 'list'
         headers['Auto-Submitted'] = 'auto-generated'
         headers['Subject'] = self.subject
         headers['From'] = (self.from_name or projname, self.from_email)

[anonymous]

Precedence "list" is also bad, as it should be filtered out by a proper mailing list manager. I definitely suggest making the header configurable in trac.ini.

[Peter Suter]

Could now be implemented as a plugin? Untested:

from trac.core import Component, implements
from trac.notification.api import IEmailDecorator
from trac.notification.mail import set_header

class ListPrecedenceEmailDecorator(Component):

    implements(IEmailDecorator)

    # IEmailDecorator methods
    
    def decorate_message(self, event, message, charset):
        set_header(message, 'Precedence', 'list', charset)

[Peter Suter]

See wiki:CookBook/Notification/Email#Addorchangeemailheader

[Ryan J Ollos]

I can confirm the mail message has precendence set to 'list' when the plugin is enabled.

[Peter Suter]

Thanks for testing!

---

What is the Precedence: header good for anyway?

​rfc:2076#section-3.9:

Sometimes used as a priority value which can influence,transmission speed and delivery. Common values are "bulk" and "first-class". Other uses is to control automatic replies and to control return-of-content facilities, and to stop mailing list loops. Non-standard (This header is not specified in any of referenced RFCs which define Internet protocols, including Internet Standards, draft standards or proposed standards. The header appears here because it often appears in e-mail or Usenet News. Usage of these headers is not in general recommended. Some header proposed in ongoing IETF standards development work, but not yet accepted, are also marked in this way.) controversial (The meaning and usage of this header is controversial, i.e. different implementors have chosen to implement the header in different ways. Because of this, such headers should be handled with caution and understanding of the different possible interpretations. ) and discouraged (This header is known to create problems and should not be generated. Handling of such headers in incoming mail should be done with great caution.).

​rfc:3834#section-3.1.8 about the Precedence: header:

A response MAY include a Precedence field in order to discourage responses from some kinds of responders which predate this specification. The field-body of the Precedence field MAY consist of the text "junk", "list", "bulk", or other text deemed appropriate by the responder. Because the Precedence field is non-standard and its interpretation varies widely, the use of Precedence is not specifically recommended by this specification, nor does this specification recommend any particular value for that field.

​Gmail Bulk Senders Guidelines:

Messages should indicate that they are bulk mail, using the 'Precedence: bulk' header field.

Introduced to Trac in #5288.