pg_xlog_watchdog

#!/usr/bin/perl

@date=localtime(time);
$date[5]+=1900;$date[4]=sprintf("%02d",++$date[4]);
$date[3]=sprintf("%02d",$date[3]);$date[2]=sprintf("%02d",$date[2]);
$date[1]=sprintf("%02d",$date[1]);$date[0]=sprintf("%02d",$date[0]);
my $pref="$date[5]-$date[4]-$date[3] $date[2]:$date[1]:$date[0] WATCHDOG ";

open LOG, '+>>', '/var/log/postgresql/watchdog.log';


sub copy()
{
    printf LOG $pref . "OK: $ARGV[0]\n";
    exit system("cp /var/lib/postgresql/9.0/main/pg_xlog/$ARGV[0] /var/lib/postgresql/9.0/main/archive/");
}

if(!$ARGV[0])
{
    printf LOG $pref . "No input args. Exit.\n";
    exit 1;
}

if ($ARGV[0]=~m/\.backup$/) { copy(); }

if (! -e "/var/lib/postgresql/9.0/main/pg_xlog/$ARGV[0]")
{
    printf LOG $pref . "WARN: no such file $ARGV[0]. Ignore\n";
    exit 0;
}

$senders_n=`ps aux|grep sender|grep -v grep|wc -l`;
chomp($senders_n);
$senders_max=`cat /etc/postgresql/9.0/main/slaves.list|egrep -v '^\$|^#'|wc -l`;
chomp($senders_max);

if ($senders_max==0) { copy(); }

if ($senders_n < $senders_max)
{
    printf LOG $pref . 'ERROR: not enough senders(' .$senders_n . ' of ' . $senders_max . ')' . "\n";
    exit 1;
}
else
{

    $connected=`ps aux|grep postg|grep sender|grep -v grep|awk '{ print \$16 }'|sed 's/([0-9]*)//g'|sort`;
    chomp($connected);
    $slaves=`cat /etc/postgresql/9.0/main/slaves.list |egrep -v '^#'|awk '{ system("host " \$1)}'|awk '{ print \$4 }'|sort`;
    chomp($slaves);
    if ($connected ne $slaves)
    {
    printf LOG $pref . "ERROR: slaves list mistmatch(unlisted slave detected)\n";
    exit 1;
    }
}

$min_pos=`ps aux|grep postgres|grep sender|grep -v grep|awk '{ print \$18 }'|sort|head -n 1`;
chomp($min_pos);
$min_pos=~s/\///;
$min_pos=~s/[\w\d]{6}$//;
$min_pos_unhex=hex($min_pos);
#printf LOG "Min pos: " . $min_pos . "\n";

$filename=$ARGV[0];
$filename=~s/(^[\w\d]{13})//;
$filename=~s/([0]{6})//;
#$filename=~s/([\w\d]$)//;

chomp($filename);
$filename_unhex=hex($filename);
#printf LOG "Filename:" .  $filename . "\n";

if ($min_pos_unhex > $filename_unhex)
{
    #printf LOG $pref . "DEBUG trying to archive $filename($filename_unhex). Current $min_pos($min_pos_unhex)\n";
    copy();
}
else
{
    printf LOG $pref . "ERROR Some senders still use this(or previous) file $ARGV[0]\n";
    exit 1;
}