The news runner is the queue runner that gateways mailing list messages to an NNTP newsgroup. One of the most important things this runner does is prepare the message for Usenet (yes, I know that NNTP is not Usenet, but this runner was originally written to gate to Usenet, which has its own rules).
>>> mlist = create_list('_xtest@example.com')
>>> mlist.linked_newsgroup = 'comp.lang.python'
Some NNTP servers such as INN reject messages containing a set of prohibited headers, so one of the things that the news runner does is remove these prohibited headers.
>>> msg = message_from_string("""\
... From: aperson@example.com
... To: _xtest@example.com
... NNTP-Posting-Host: news.example.com
... NNTP-Posting-Date: today
... X-Trace: blah blah
... X-Complaints-To: abuse@dom.ain
... Xref: blah blah
... Xref: blah blah
... Date-Received: yesterday
... Posted: tomorrow
... Posting-Version: 99.99
... Relay-Version: 88.88
... Received: blah blah
...
... A message
... """)
>>> msgdata = {}
>>> from mailman.queue.news import prepare_message
>>> prepare_message(mlist, msg, msgdata)
>>> msgdata['prepped']
True
>>> print msg.as_string()
From: aperson@example.com
To: _xtest@example.com
Newsgroups: comp.lang.python
Message-ID: ...
Lines: 1
<BLANKLINE>
A message
<BLANKLINE>
Some NNTP servers will reject messages where certain headers are duplicated, so the news runner must collapse or move these duplicate headers to an X-Original-* header that the news server doesn’t care about.
>>> msg = message_from_string("""\
... From: aperson@example.com
... To: _xtest@example.com
... To: two@example.com
... Cc: three@example.com
... Cc: four@example.com
... Cc: five@example.com
... Content-Transfer-Encoding: yes
... Content-Transfer-Encoding: no
... Content-Transfer-Encoding: maybe
...
... A message
... """)
>>> msgdata = {}
>>> prepare_message(mlist, msg, msgdata)
>>> msgdata['prepped']
True
>>> print msg.as_string()
From: aperson@example.com
Newsgroups: comp.lang.python
Message-ID: ...
Lines: 1
To: _xtest@example.com
X-Original-To: two@example.com
CC: three@example.com
X-Original-CC: four@example.com
X-Original-CC: five@example.com
Content-Transfer-Encoding: yes
X-Original-Content-Transfer-Encoding: no
X-Original-Content-Transfer-Encoding: maybe
<BLANKLINE>
A message
<BLANKLINE>
But if no headers are duplicated, then the news runner doesn’t need to modify the message.
>>> msg = message_from_string("""\
... From: aperson@example.com
... To: _xtest@example.com
... Cc: someother@example.com
... Content-Transfer-Encoding: yes
...
... A message
... """)
>>> msgdata = {}
>>> prepare_message(mlist, msg, msgdata)
>>> msgdata['prepped']
True
>>> print msg.as_string()
From: aperson@example.com
To: _xtest@example.com
Cc: someother@example.com
Content-Transfer-Encoding: yes
Newsgroups: comp.lang.python
Message-ID: ...
Lines: 1
<BLANKLINE>
A message
<BLANKLINE>
When the newsgroup is moderated, an Approved: header with the list’s posting address is added for the benefit of the Usenet system.
>>> from mailman.interfaces.nntp import NewsModeration
>>> mlist.news_moderation = NewsModeration.open_moderated
>>> msg = message_from_string("""\
... From: aperson@example.com
... To: _xtest@example.com
... Approved: this gets deleted
...
... """)
>>> prepare_message(mlist, msg, {})
>>> print msg['approved']
_xtest@example.com
>>> mlist.news_moderation = NewsModeration.moderated
>>> msg = message_from_string("""\
... From: aperson@example.com
... To: _xtest@example.com
... Approved: this gets deleted
...
... """)
>>> prepare_message(mlist, msg, {})
>>> print msg['approved']
_xtest@example.com
But if the newsgroup is not moderated, the Approved: header is not changed.
>>> mlist.news_moderation = NewsModeration.none
>>> msg = message_from_string("""\
... From: aperson@example.com
... To: _xtest@example.com
... Approved: this doesn't get deleted
...
... """)
>>> prepare_message(mlist, msg, {})
>>> msg['approved']
u"this doesn't get deleted"
XXX More of the NewsRunner should be tested.