Digesting

Mailman crafts and sends digests by a separate digest runner process. This starts by a number of messages being posted to the mailing list.

>>> mlist = create_list('test@example.com')
>>> mlist.digest_size_threshold = 0.6
>>> mlist.volume = 1
>>> mlist.next_digest_number = 1
>>> mlist.send_welcome_message = False

>>> from string import Template
>>> process = config.handlers['to-digest'].process

>>> def fill_digest():
...     size = 0
...     for i in range(1, 5):
...         text = Template("""\
... From: aperson@example.com
... To: xtest@example.com
... Subject: Test message $i
... List-Post: <test@example.com>
...
... Here is message $i
... """).substitute(i=i)
...         msg = message_from_string(text)
...         process(mlist, msg, {})
...         size += len(text)
...         if size >= mlist.digest_size_threshold * 1024:
...             break

>>> fill_digest()

The runner gets kicked off when a marker message gets dropped into the digest queue. The message metadata points to the mailbox file containing the messages to put in the digest.

>>> digestq = config.switchboards['digest']
>>> len(digestq.files)
1

>>> from mailman.testing.helpers import get_queue_messages
>>> entry = get_queue_messages('digest')[0]

The marker message is empty.

>>> print(entry.msg.as_string())

But the message metadata has a reference to the digest file.

>>> dump_msgdata(entry.msgdata)
_parsemsg    : False
digest_number: 1
digest_path  : .../lists/test@example.com/digest.1.1.mmdf
listid       : test.example.com
version      : 3
volume       : 1

There are 4 messages in the digest.

>>> from mailman.utilities.mailbox import Mailbox
>>> sum(1 for item in Mailbox(entry.msgdata['digest_path']))
4

When the runner runs, it processes the digest mailbox, crafting both the plain text (RFC 1153) digest and the MIME digest.

>>> from mailman.runners.digest import DigestRunner
>>> from mailman.testing.helpers import make_testable_runner
>>> runner = make_testable_runner(DigestRunner)
>>> runner.run()

If there are no members receiving digests, none are sent.

>>> messages = get_queue_messages('virgin')
>>> len(messages)
0

Once some users are subscribed and receiving digests, the digest runner places both digests into the virgin queue for final delivery.

>>> from mailman.testing.helpers import subscribe
>>> from mailman.interfaces.member import DeliveryMode

>>> anne = subscribe(mlist, 'Anne')
>>> anne.preferences.delivery_mode = DeliveryMode.mime_digests
>>> bart = subscribe(mlist, 'Bart')
>>> bart.preferences.delivery_mode = DeliveryMode.plaintext_digests

>>> fill_digest()
>>> runner.run()
>>> messages = get_queue_messages('virgin')
>>> len(messages)
2

Anne and Bart unsubscribe from the mailing list.

>>> anne.unsubscribe()
>>> bart.unsubscribe()

The MIME digest is a multipart, and the RFC 1153 digest is the other one.

>>> def mime_rfc1153(messages):
...     if messages[0].msg.is_multipart():
...         return messages[0], messages[1]
...     return messages[1], messages[0]

>>> mime, rfc1153 = mime_rfc1153(messages)

The MIME digest has lots of good stuff, all contained in the multipart.

>>> print(mime.msg.as_string())
Content-Type: multipart/mixed; boundary="===============...=="
MIME-Version: 1.0
From: test-request@example.com
Subject: Test Digest, Vol 1, Issue 2
To: test@example.com
Reply-To: test@example.com
Date: ...
Message-ID: ...

--===============...==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Description: Test Digest, Vol 1, Issue 2

Send Test mailing list submissions to
    test@example.com

To subscribe or unsubscribe via the World Wide Web, visit
    http://lists.example.com/listinfo/test@example.com
or, via email, send a message with subject or body 'help' to
    test-request@example.com

You can reach the person managing the list at
    test-owner@example.com

When replying, please edit your Subject line so it is more specific
than "Re: Contents of Test digest..."

--===============...==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Description: Today's Topics (4 messages)

Today's Topics:

   1. Test message 1 (aperson@example.com)
   2. Test message 2 (aperson@example.com)
   3. Test message 3 (aperson@example.com)
   4. Test message 4 (aperson@example.com)

--===============...==
Content-Type: message/rfc822
MIME-Version: 1.0

From: aperson@example.com
To: xtest@example.com
Subject: Test message 1
List-Post: <test@example.com>

Here is message 1

--===============...==
Content-Type: message/rfc822
MIME-Version: 1.0

From: aperson@example.com
To: xtest@example.com
Subject: Test message 2
List-Post: <test@example.com>

Here is message 2

--===============...==
Content-Type: message/rfc822
MIME-Version: 1.0

From: aperson@example.com
To: xtest@example.com
Subject: Test message 3
List-Post: <test@example.com>

Here is message 3

--===============...==
Content-Type: message/rfc822
MIME-Version: 1.0

From: aperson@example.com
To: xtest@example.com
Subject: Test message 4
List-Post: <test@example.com>

Here is message 4

--===============...==
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Description: Digest Footer

_______________________________________________
Test mailing list
test@example.com
http://lists.example.com/listinfo/test@example.com

--===============...==--

The RFC 1153 contains the digest in a single plain text message.

>>> print(rfc1153.msg.as_string())
From: test-request@example.com
Subject: Test Digest, Vol 1, Issue 2
To: test@example.com
Reply-To: test@example.com
Date: ...
Message-ID: ...
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit

Send Test mailing list submissions to
    test@example.com

To subscribe or unsubscribe via the World Wide Web, visit
    http://lists.example.com/listinfo/test@example.com
or, via email, send a message with subject or body 'help' to
    test-request@example.com

You can reach the person managing the list at
    test-owner@example.com

When replying, please edit your Subject line so it is more specific
than "Re: Contents of Test digest..."

Today's Topics:

   1. Test message 1 (aperson@example.com)
   2. Test message 2 (aperson@example.com)
   3. Test message 3 (aperson@example.com)
   4. Test message 4 (aperson@example.com)


----------------------------------------------------------------------

From: aperson@example.com
Subject: Test message 1
To: xtest@example.com

Here is message 1

------------------------------

From: aperson@example.com
Subject: Test message 2
To: xtest@example.com

Here is message 2

------------------------------

From: aperson@example.com
Subject: Test message 3
To: xtest@example.com

Here is message 3

------------------------------

From: aperson@example.com
Subject: Test message 4
To: xtest@example.com

Here is message 4

------------------------------

Subject: Digest Footer

_______________________________________________
Test mailing list
test@example.com
http://lists.example.com/listinfo/test@example.com


------------------------------

End of Test Digest, Vol 1, Issue 2
**********************************

Digest delivery

A mailing list’s members can choose to receive normal delivery, plain text digests, or MIME digests.

>>> len(get_queue_messages('virgin'))
0

>>> from mailman.interfaces.usermanager import IUserManager
>>> from zope.component import getUtility
>>> user_manager = getUtility(IUserManager)

>>> from mailman.interfaces.member import DeliveryMode, MemberRole
>>> def subscribe(email, mode):
...     address = user_manager.create_address(email)
...     member = mlist.subscribe(address, MemberRole.member)
...     member.preferences.delivery_mode = mode
...     return member

Two regular delivery members subscribe to the mailing list.

>>> member_1 = subscribe('uperson@example.com', DeliveryMode.regular)
>>> member_2 = subscribe('vperson@example.com', DeliveryMode.regular)

Two MIME digest members subscribe to the mailing list.

>>> member_3 = subscribe('wperson@example.com', DeliveryMode.mime_digests)
>>> member_4 = subscribe('xperson@example.com', DeliveryMode.mime_digests)

One RFC 1153 digest member subscribes to the mailing list.

>>> member_5 = subscribe(
...     'yperson@example.com', DeliveryMode.plaintext_digests)
>>> member_6 = subscribe(
...     'zperson@example.com', DeliveryMode.plaintext_digests)

When a digest gets sent, the appropriate recipient list is chosen.

>>> mlist.preferred_language = 'en'
>>> mlist.digest_size_threshold = 0.5
>>> fill_digest()
>>> runner.run()

The digests are sitting in the virgin queue. One of them is the MIME digest and the other is the RFC 1153 digest.

>>> messages = get_queue_messages('virgin')
>>> len(messages)
2

>>> mime, rfc1153 = mime_rfc1153(messages)

Only wperson and xperson get the MIME digests.

>>> sorted(mime.msgdata['recipients'])
['wperson@example.com', 'xperson@example.com']

Only yperson and zperson get the RFC 1153 digests.

>>> sorted(rfc1153.msgdata['recipients'])
['yperson@example.com', 'zperson@example.com']

Now uperson decides that they would like to start receiving digests too.

>>> member_1.preferences.delivery_mode = DeliveryMode.mime_digests
>>> fill_digest()
>>> runner.run()

>>> messages = get_queue_messages('virgin')
>>> len(messages)
2

>>> mime, rfc1153 = mime_rfc1153(messages)
>>> sorted(mime.msgdata['recipients'])
['uperson@example.com', 'wperson@example.com', 'xperson@example.com']

>>> sorted(rfc1153.msgdata['recipients'])
['yperson@example.com', 'zperson@example.com']

At this point, both uperson and wperson decide that they’d rather receive regular deliveries instead of digests. uperson would like to get any last digest that may be sent so that she doesn’t miss anything. wperson does care as much and does not want to receive one last digest.

>>> mlist.send_one_last_digest_to(
...     member_1.address, member_1.preferences.delivery_mode)

>>> member_1.preferences.delivery_mode = DeliveryMode.regular
>>> member_3.preferences.delivery_mode = DeliveryMode.regular

>>> fill_digest()
>>> runner.run()

>>> messages = get_queue_messages('virgin')
>>> mime, rfc1153 = mime_rfc1153(messages)
>>> sorted(mime.msgdata['recipients'])
['uperson@example.com', 'xperson@example.com']

>>> sorted(rfc1153.msgdata['recipients'])
['yperson@example.com', 'zperson@example.com']

Since uperson has received their last digest, they will not get any more of them.

>>> fill_digest()
>>> runner.run()

>>> messages = get_queue_messages('virgin')
>>> len(messages)
2

>>> mime, rfc1153 = mime_rfc1153(messages)
>>> sorted(mime.msgdata['recipients'])
['xperson@example.com']

>>> sorted(rfc1153.msgdata['recipients'])
['yperson@example.com', 'zperson@example.com']