handle DiscardMessage in ToDigest handler

[mbp]

Our scrubber was raising DiscardMessage exceptions when
trying to scrub messages from the digest. This
situation may have arisen because of a configuration
change that allowed some messages to get into the
digest mailbox when they would previously have been
scrubbed out.

In any case, it was causing exceptions like this:

Traceback (most recent call last):
  File "/usr/local/mailman/cron/senddigests", line 94, in ?
    main()
  File "/usr/local/mailman/cron/senddigests", line 86,
in main
    mlist.send_digest_now()
  File "/usr/local/mailman/Mailman/Digester.py", line
60, in send_digest_now
    ToDigest.send_digests(self, mboxfp)
  File
"/usr/local/mailman/Mailman/Handlers/ToDigest.py", line
131, in send_digests
    send_i18n_digests(mlist, mboxfp)
  File
"/usr/local/mailman/Mailman/Handlers/ToDigest.py", line
304, in send_i18n_digests
    msg = scrubber(mlist, msg)
  File
"/usr/local/mailman/Mailman/Handlers/Scrubber.py", line
178, in process
    raise DiscardMessage
Mailman.Errors.DiscardMessage

It seems reasonable to have the ToDigest handler
respond to these exceptions by discarding the message,
per this patch

--- ToDigest.py.orig Mon Dec 15 02:21:51 2003
+++ ToDigest.py Mon Dec 15 02:23:19 2003
@@ -44,6 +44,7 @@
 from Mailman import Utils
 from Mailman import Message
 from Mailman import i18n
+from Mailman import Errors
 from Mailman.Mailbox import Mailbox
 from Mailman.MemberAdaptor import ENABLED
 from Mailman.Handlers.Decorate import decorate
@@ -301,7 +302,10 @@
             print >> plainmsg, separator30
             print >> plainmsg
         # Use Mailman.Handlers.Scrubber.process() to
get plain text
- msg = scrubber(mlist, msg)
+ try:
+ msg = scrubber(mlist, msg)
+ except (Errors.DiscardMessage):
+ continue
         # Honor the default setting
         for h in mm_cfg.PLAIN_DIGEST_KEEP_HEADERS:
             if msg[h]: