[Mailman-Developers] [Patch] [long] Reply-To munging: stop the madness

[Joseph Knapka]

And by "the madness", I mean the fact that I've seen more list traffic
devoted to reply-to munging in the past year than to any other single
subject. That's just silly; but Reply-To flamewars seem to break out
every three months or so on every list I'm subscribed to. It's a
tragic waste of bandwidth.

It seems to me that the obvious way to make everyone happy is to make
the presence of "Reply-To: list" headers a per-subscriber option. I
have implemented something simple that achieves this goal in a fairly
icky way; patch and explanation below. However, the main purpose of
this message is to suggest that in some future Mailman release,
"Reply-To: list" be a subscriber-centric option rather than a
list-centric one.

---

The patch below permits a list's accept_these_nonmembers attribute to
contain entries of the form "^+listname", which causes Mailman to
assume, for post-moderation purposes, that all subscribers to
"listname" are also subscribed to the list being managed. For example,
if list A's accept_these_nonmembers contains ^+B, then all
subscribers to B will be allowed to post to A. This permits the
following (suboptimal) solution to the Reply-To munging controversy:

   For each list L for which L.reply_goes_to_list="This list", create
   a second list L-no-reply-to with L-no-reply-to.reply_goes_to_list="Poster".

   Add L-no-reply-to to L's subscriber list.

   Add ^+L-no-reply-to to L.accept_these_nonmembers.

   Add ^+L to L-no-reply-to.accept_these_nonmembers.

Now, anyone who doesn't want to get Reply-To headers subscribes to
L-no-reply-to instead of L. Everyone still posts to L, however, and
all traffic posted to L appears on both lists. Due to the ^+ options,
anyone subscribed to either list can post to L and have their posts
picked up by L-no-reply-to.  (Of course, we could have allowed
nonsubscribers to post to both lists, but no one on the particular
list for which I produced these patches wanted to do that, due to spam
problems.)

This is obviously a less-than-perfect solution, which is why I'm
suggesting it be done differently in a future release. I'm willing
to look into implementing Reply-To as a subscriber option, but
I may not have time to do so.

Here are the patches, to GUIBase.py and Moderate.py. The patch
to GUIBase.py simply relaxes the input validation to allow
the ^+listname entries; the Moderate.py patch implements the
additional moderation logic.

===File /usr/local/mailman/GUIBase.py.diff==================
--- /usr/local/mailman/src/mailman-2.1.1/Mailman/Gui/GUIBase.py	2002-08-14 18:02:27.000000000 -0600
+++ GUIBase.py	2003-04-21 07:16:55.000000000 -0600
@@ -73,10 +73,11 @@
                     # See if this is a context that accepts regular
                     # expressions, and that the re is legal
                     if wtype == mm_cfg.EmailListEx and addr.startswith('^'):
-                        try:
-                            re.compile(addr)
-                        except re.error:
-                            raise ValueError
+                        if not addr.startswith('^+'):
+                            try:
+                                re.compile(addr)
+                            except re.error:
+                                raise ValueError
                     else:
                         raise
                 addrs.append(addr)
============================================================

===File /usr/local/mailman/Moderate.py.diff=================
--- /usr/local/mailman/src/mailman-2.1.1/Mailman/Handlers/Moderate.py	2002-12-30 20:28:41.000000000 -0700
+++ Moderate.py	2003-04-21 09:43:18.000000000 -0600
@@ -16,7 +16,6 @@
 
 """Posting moderation filter.
 """
-
 import re
 from email.MIMEMessage import MIMEMessage
 from email.MIMEText import MIMEText
@@ -28,6 +27,7 @@
 from Mailman.i18n import _
 from Mailman.Handlers import Hold
 from Mailman.Logging.Syslog import syslog
+import Mailman.MailList
 
 
 
@@ -115,14 +115,27 @@
 
 
 def matches_p(sender, nonmembers):
-    # First strip out all the regular expressions
-    plainaddrs = [addr for addr in nonmembers if not addr.startswith('^')]
+    # First do list inclusions.
+    incAdd = []
+    for linc in nonmembers:
+        if linc.startswith('^+'):
+            otherListName = linc[2:]
+            try:
+                otherList = Mailman.MailList.MailList(otherListName,lock=0)
+                otherMembers = otherList.getMembers()
+                incAdd = incAdd + otherMembers
+            except:
+                syslog.write("Moderator","Could not process list inclusion %s"%otherListName)
+                pass
+    nonmembers = nonmembers+incAdd
+    # Strip out all the regular expressions and list inclusions
+    plainaddrs = [addr for addr in nonmembers if not addr.startswith('^')] 
     addrdict = Utils.List2Dict(plainaddrs, foldcase=1)
     if addrdict.has_key(sender):
         return 1
     # Now do the regular expression matches
     for are in nonmembers:
-        if are.startswith('^'):
+        if are.startswith('^') and not are.startswith('^+'):
             try:
                 cre = re.compile(are, re.IGNORECASE)
             except re.error:
============================================================

Cheers,

-- Joe Knapka