Ramblings

Sometimes when you are working with a bug tracking system you want to see the bugs as they appear or heavy changes are done. This was the case with me and a project I'm working on and without finding anyone else having done the same I took the challenge.

The goal was to show new bugs appearing and changes done to them in an IRC channel. I had already an eggdrop bot running there and I needed to somehow connect Bugzilla with it.

1. I started out by adding a QA contact in bugzilla which gets all new bugs and changes done to them.

2. Then I had to configure exim4 to send email received to a script that could communicate with eggdrop. As it turned out, I simply let the script add each mail message as a file in an explicit catalogue.

Exim config: /etc/exim4/exim4.conf.template

bugs_router:
  driver = accept # accept the mail

  # the following two lines makes it get email sent to bugzilla@bugs.domain.com
  local_parts = bugzilla # username it should answer to
  domains = bugs.domain.com # which domain it should answer to

  senders = bugzilla-daemon@bugzillahost.com # Only mail sent from bugzilla
  transport = bugs_transport # which transport should take care of the mail

# ...

bugs_transport:
  driver = pipe # pipe the mail content to a command
  command = /home/bugsuser/scripts/bugzillahandler.pl
  user = bugsuser # run as this user
  group = bugsuser
  return_output # fail on output
  log_output

Then the script that puts the mail messages in individual files looked like this:

/home/bugsuser/scripts/bugzillahandler.pl:

#!/usr/bin/perl
use strict;
use warnings;

my $ts = time();

if (open(my $out, ">", "/var/log/bugzillahandler/$ts")) {
  local $/;
  print $out (<>);
  close($out) or die "Cannopt close $ts: $!";
} else {
  die "cannot open $ts for >: $!";
}

3. Now the eggdrop has to get these files somehow and I add a timer based part that runs whenever the eggdrop is online in a script file included in the eggdrop:

# this code basically calls a perl script every 60 seconds 
# and outputs its output to the channel

set interval 60
set channel "#bugsoutput"

# delete existing timers
foreach t [utimers] {
  if {[lindex $t 1] == "checkbugzilla"} {
    killutimer [lindex $t end]
  }
}

# set up a new timer
set bugzillatimer [utimer $interval checkbugzilla]

# function that is called
proc checkbugzilla {} {
  global interval channel
  set ret "[exec /home/bugsuser/eggdrop/scripts/perl/checkbugzilla.pl]"
    if {$ret != 0} {
    set lines [split "$ret" "\n"]
    foreach line $lines {
      # output each line as one line to the irc channel
      putquick "NOTICE $channel :$line"
    }
  }
  # set up next call
  set bugzillatimer [utimer $interval checkbugzilla]
}

4. Finally the perl script that parses the files and outputs them in a nice fashion, one line per bug that has appeared since last time.

/home/bugsuser/eggdrop/scripts/perl/checkbugzilla.pl:

#!/usr/bin/perl
# get all the files that have changed since last time we checked (1 minute)
$files = `find /var/log/bugzillahandler -mmin -1 \! -type d`;
foreach $file (split/\n/,$files) {
  if(open(IN,$file)) {
    # open the file and read out its content.
    my $content;
    while(<IN>) {
      $content .= $_;
    }
    close(IN);

    # do some crude pattern matching to get out info about new bugs 
    # and bugs that have changed to or from RESOLVED state.

    ($head, $body) = split(/\n\n/,$content,2);
    $head =~ /^Subject:\s*(.*)$/mgi;
    $subject = $1;
    $subject =~ /\[Bug (\d+)\]/mgi;
    $bugnum = $1;
    $subject =~ s/\s*\[.*?\]\s*//mgi;
    $subject = trim($subject);
    if ($subject =~ /New/mgi) {
      $body =~ /Product: (.*?)\s*$/mgi;
      $product = $1;
      $body =~ /Component: (.*?)\s*$/mgi;
      $component = $1;
      $body =~ /ReportedBy: (.*?)\s*$/mgi;
      $reporter = $1;
      $out .= "[Bug $bugnum] $subject <$product/$component> ($reporter)".
              " | http://bugzillahost.com/bugzilla/show_bug.cgi?id=$bugnum\n";
    } elsif ($body =~ /Status\|([^\|]+?)\|([^|]+?)$/mgi) {
      $from_status = trim($1);
      $to_status = trim($2);
      $resolution = "";
      if ($body =~ /Resolution\|([^\|]+?)\s*\|([^|]+?)\s*$/mgi) {
        $from_resolution = trim($1);
        $to_resolution = trim($2);
        if ($to_status eq "RESOLVED") {
          $resolution = "$to_resolution: ";
        }
      }
      # populate output buffer
      $out .= "[Bug $bugnum] $to_status: $resolution$subject".
              " | http://bugzillahost.com/bugzilla/show_bug.cgi?id=$bugnum\n";
    }
  }
}

# if there is no output print out a single "0" to let 
# the eggdrop part know it shouldn't do anything.
if ($out ne "") {
  print $out;
} else {
  print "0";
}
exit(0);

sub trim($) {
  # remove whitespaces in front and behind a string
  my $string = shift;
  $string =~ s/^\s+//;
  $string =~ s/\s+$//;
  return $string;
}

5. Voilá, a bot that outputs bug information automatically.

07:45 [Bug 1234] New: There is an error <Coffemaker/filter_obj> \
(reporter@customer.com) | http://bugzillahost.com/bugzilla/show_bug.cgi?id=1234

Most of the scripts are kind of patchwork evolved while experimenting. They could all have been smaller and smarter, and also fewer steps. However, this solution worked and I didn't feel like fixing it. (If it works don't fix it).

If you want to suggest improvements I'm all ears though. Hopefully some of you will find this useful. I felt I had to write it down somewhere at least so that next time I need to add something I don't have to go back and decipher it.