It would be nice if mails sent by bugzilla can be grouped by MUAs into threads. This needs only small changes in bugzilla (I guess ;)) and can be reached by adding a 'References:' header pointing to the [New]-mail. You can add an extra column to the database storing the msg-id of the [New]-mail, but it would be more easy if this mail gets a msg-id like Message-ID: <bugzilla-#bugid.com> which should be an unique value. [Changed] mails don't need a special msg-id; it can be still assigned by the MTA. They need only a header like References: <bugzilla-#bugid.com>
This schema would only work is the "New" message is still around. What if you have deleted it? What if you have added yourself to the CC list and never saw the "New" message? My proposal is in each mail to include: Message-Id: <bugzilla-bugid-serial.com> References: <bugzilla-bugid-"serial - 1"@bugzilla.redhat.com> (or even: References: <bugzilla-bugid-"serial - 1"@bugzilla.redhat.com> <bugzilla-bugid-"serial - 2"@bugzilla.redhat.com> <bugzilla-bugid-"serial - 3"@bugzilla.redhat.com> ) where "serial" is the number of bugmail that were sent for this bug. This way every bugmail will be filed in a MUA as a response to the previous bugmail (or several previous bugmails) from the same bug, which is what it usually is.
How would I obtain this "serial" number based on how Bugzilla is currently sending out mail. Currently it opens a pipe to /usr/lib/sendmail -t and cats a preformatted message to the pipe. Is there way to retrieve the serial number? I will admit to not being a mail expert.
The serial number is the count of comments; the initial report has a serial of '0'. This value is already in use (e.g. in | https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=50113#c2 ~ ), is available inside bugzilla and has nothing to do with the mailing-process.
Special messages which do depend on a new comment (e.g. changed dependencies) should not have a Message-Id given by bugzilla. (Or bugzilla should use an internal counter to create unique Message-Id's; but because sendmail creates good Message-Id's when the message does not contain a such one already, this will be unnecessary work IMHO). I am not sure if | References: <bugzilla-<bugid>-0@....> or | References: <bugzilla-<bugid>-<# of comments - 1>@...> should be used in this case; I would prefer the first version.
Re: comment #4. I actually think that *both* should be used - e.g. References: <bugzilla-<bugid>-0@....>, <bugzilla-<bugid>-<# of comments - 1>@...> (or may be even 3 or 4 references - 0 and previous 2 or 3). The reason is that - user may have deleted the first message - CC users may have never gotten the first message at all.
revisiting, since In-Reply-To: bugzilla-<bugid>@redhat.com doesnt seem to be suiting everyone due to MUA differences.
Changes have been made to fix this problem. Please reopen this bug if not the case for you.