I have not had time to do the test “postfix memcached patch” because there are no idle servers that can be used for the experiment. instead, I’ve made a tutorial how to integrate memcached as a “postfix lookup table” with the help of tcp_table and a simple perl script.
Indeed, tcp_table “table lookup protocol” is one of the most powerful tools as well as the regexp and pcre, in my opinion. although client-server connection is not protected and and the server is not authenticated.
yes, I did a lot of experiments using tcp_table and perl scripts. it made me realize that I can do almost everything I need and make postfix as my favorite MTA.
Things required:
- perl Cache::Memcached module
- memcached
- postfix with tcp_table support
OK, first we create a simple perl script that allows you to handle the protocols of tcp_table. let’s call it memc.pl
#!/usr/bin/perl
use strict;
use warnings;
use Sys::Syslog qw(:DEFAULT setlogsock);
use Cache::Memcached;
# Configure the memcached server
my $memd = new Cache::Memcached {
'servers' => [ '127.0.0.1:11211' ],
};
#
# Initalize and open syslog.
#
openlog('postfix/memcached','pid','mail');
sub qrymemc {
return unless /^get\s+(.+)/i;
my $kmemc = lc($1);
chomp($kmemc);
trim($kmemc);
my $vmemc = $memd->get($kmemc);
if (defined $vmemc) {
return ($kmemc,$vmemc);
}
return;
}
sub trim{
$_[0]=~s/^\s+//;
$_[0]=~s/\s+$//;
return;
}
#
# Autoflush standard output.
#
select STDOUT; $|++;
while (<>) {
chomp;
if (/^get\s+(.+)/i) {
my $data = lc($1);
my @res = qrymemc($data);
syslog("info","data: %s", $data);
if (@res) {
chomp(@res);
print "200 $res[1]\n";
syslog("info","Found: key = %s, value = %s", $res[0], $res[1]);
next;
}
}
print "200 DUNNO\n";
}