Lists with topics enabled can throw unexpected keyword argument 'Delete' exception.

Fixed upstream, but needs backport to Trusty - all other releases are already including the fix.

The diff this is about is:
@@ -71,7 +73,7 @@
     if hits:
         msgdata['topichits'] = hits.keys()
         change_header('X-Topics', NLTAB.join(hits.keys()),
- mlist, msg, msgdata, Delete=False)
+ mlist, msg, msgdata, delete=False)

FYI - it was reported that: "This is a high importance bug that can cause email to "disappear" since Mailman gets an exception and just puts the email into the shunt directory."

by Phillip Colmer

It feels I'm the only one coming by to clean every now and then - feels bad :-/
The change was revno: 1433

For the sake of any progress I made a ppa with the fix available at [1].

I thought lacking the experience to set it up correctly I can't drive a SRU [2]
But actually, this is easy enough just by looking at the code:

That should be enough I'd think:
$ grep -A 2 'change_header(' Mailman/Handlers/Tagger.py; grep -A 2 def Mailman/Handlers/CookHeaders.py | grep 'change_header('
        change_header('X-Topics', NLTAB.join(hits.keys()),
                      mlist, msg, msgdata, Delete=False)
def change_header(name, value, mlist, msg, msgdata, delete=True, repl=True):

@Mark - if you have not given up on this bug, if you can provide a "steps to reproduce" please feel free to add.

[1]: https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/3011
[2]: https://wiki.ubuntu.com/StableReleaseUpdates

I think the fix is obvious, but the case a bit special without (me) knowing how to reproduce. So an MP for review comments is up at [1] to gain more confidence before uploading for an SRU.

[1]: https://code.launchpad.net/~paelzer/ubuntu/+source/mailman/+git/mailman/+merge/332798

To reproduce the error you need to enable topics for a list, create a topic and send a post that matches that topic.

You can do the enable/create by putting these two lines

topics_enabled = 1
topics = [('Match_all', '.', 'Topic matches anything for testing', False)]

in a file and running Mailman's bin/config_list like

bin/config_list -i path/to/file/with/lines list_name

Then, a post to that list should be delivered normally and contain a header 'X-Topics: Match_all', but the bug will cause the post to be shunted.

Got an ack on the MP and pushed the fix to Trusty as SRU.
Somewhat sad but better late than never.

Hello Mark, or anyone else affected,

Accepted mailman into trusty-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/mailman/1:2.1.16-2ubuntu0.3 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested and change the tag from verification-needed-trusty to verification-done-trusty. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-trusty. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

I have tested 2.1.16 on trusty and I can confirm that it replaces "Delete=False" with "delete=False" in /var/lib/mailman/Mailman/Handlers/Tagger.py.

Also chacked the same, thanks Phillip!
Setting verified.

This bug was fixed in the package mailman - 1:2.1.16-2ubuntu0.3

---------------
mailman (1:2.1.16-2ubuntu0.3) trusty; urgency=medium

  * Fixed a misspelling in Tagger.py that breaks Lists
    with topics enabled (LP: #1251495)

 -- Christian Ehrhardt <email address hidden> Wed, 25 Oct 2017 16:46:47 +0200

The verification of the Stable Release Update for mailman has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.