#!/usr/bin/perl
$|=1;
# The LearningOnline Network with CAPA
# Cluster Status
# (Versions
# (Running loncron
# 09/06/01 Gerd Kortemeyer)
# 02/18/02,02/19/02 Gerd Kortemeyer)

use lib '/home/httpd/lib/perl/';
use LONCAPA::Configuration;

use LWP::UserAgent();
use HTTP::Headers;
use IO::File;

my %host=();
my $oneday=60*60*24;

my %connectionstatus=();

sub key {
    my ($local,$url)=@_;
    my $key=$local.'_'.$url;
    $key=~s/\W/\_/gs;
    return $key;
}

sub hidden {
    my ($name,$value)=@_;
    print "\n<input type='hidden' name='$name' value='$value' />";
}

sub request {
    my ($local,$url,$cachetime)=@_;
    my $key=&key($local,$url);
    my $reply='';
    if ($FORM{$key.'_time'}) {
	if ((time-$FORM{$key.'_time'})<$cachetime) {
	    $reply=$FORM{$key};
	    &hidden($key.'_time',$FORM{$key.'_time'});
	    &hidden($key.'_fromcache',1);
	}
    }
    unless ($reply) {
	unless ($hostname{$local}) { 
	    $reply='local_unknown'; 
	} else {

	    my $ua=new LWP::UserAgent(timeout => 20);
    
	    my $request=new HTTP::Request('GET',
					  "http://".$hostname{$local}.$url);
	    $request->authorization_basic('lonadm','litelite');

	    my $response=$ua->request($request);

	    unless ($response->is_success) { 
		$reply='local_error'; 
	    } else {
		$reply=$response->content;
		chomp($reply);
	    }
	}
	&hidden($key.'_time',time);
    }
    &hidden($key,$reply);
    return $reply;
}

# ============================================= Are local and remote connected?
sub connected {
    my ($local,$remote)=@_;
    $local=~s/\W//g;
    $remote=~s/\W//g;

    unless ($hostname{$remote}) { return 'remote_unknown'; }
    my $url='/cgi-bin/ping.pl?'.$remote;
#
# Slowly phase this in: if not cached, only do 10 percent of the cases 
#
    unless ($FORM{&key($local,$url)}) {
	unless (rand>0.9) { return 'not_yet'; }
    }
#
# Actually do the query
#
    &statuslist($local,'connecting '.$remote);
    my $reply=&request($local,$url,1800);
    $reply=(split("\n",$reply))[0];
    $reply=~s/\W//g;
    if ($reply ne $remote) { return $reply; }
    return 'ok';
}
# ============================================================ Get a reply hash

sub replyhash {
    my %returnhash=();
    foreach (split(/\&/,&request(@_))) {
	my ($name,$value)=split(/\=/,$_);
	if ($name) {
	    unless ($value) { $value=''; }
	    $returnhash{$name}=$value;
	}
    }
    return %returnhash;
}

# ========================================================== Show server status

sub otherwindow {
    my ($local,$url,$label)=@_;
    return
  "<a href='http://$hostname{$local}$url' target='newwin$local'>$label</a>";
}

sub serverstatus {
    my $local=shift;
    print "\n<hr /><h3>$local $hostdom{$local} ($hostname{$local}; $hostrole{$local})</h3>\n";
# checkrpms
    if ($host{$local.'_checkrpms'}) {
	print "<br />RPMs: ".$host{$local.'_checkrpms'}
    }
# mysql
    if ($host{$local.'_mysql'}) {
	print "<br />MySQL Database: ".$host{$local.'_mysql'}
    }
}

# ====================================================================== Status
sub statuslist {
    my ($local,$what)=@_;
    print 
"<script>document.prgstat.progress.value='Testing $local ($hostname{$local}): $what';</script>\n";
}

#
# Main program
#
# ========================================================= Get form parameters
my $buffer;

read(STDIN, $buffer, $ENV{'CONTENT_LENGTH'});
my @pairs=split(/&/,$buffer);
my $pair; my $name; my $value;
undef %FORM;
%FORM=();
foreach $pair (@pairs) {
    ($name,$value) = split(/=/,$pair);
    $value =~ tr/+/ /;
    $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
    $FORM{$name}=$value;
} 

$buffer=$ENV{'QUERY_STRING'};
@pairs=split(/&/,$buffer);
foreach $pair (@pairs) {
    ($name,$value) = split(/=/,$pair);
    $value =~ tr/+/ /;
    $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
    $FORM{$name}=$value;
} 

# ====================================================== Determine refresh rate

my $refresh=(($FORM{'refresh'}=~/^\d+$/)?$FORM{'refresh'}:60);
if ($refresh<30) { $refresh=30; }
my $starttime=time;
# ================================================================ Send Headers
print "Content-type: text/html\n\n".
    "<html><body bgcolor=#FFFFFF>\n";
# -------------------- Read loncapa.conf (and by default, loncapa_apache.conf).
my $perlvarref=LONCAPA::Configuration::read_conf('loncapa.conf');
my %perlvar=%{$perlvarref};
undef $perlvarref; # remove since sensitive and not needed
delete $perlvar{'lonReceipt'}; # remove since sensitive and not needed
delete $perlvar{'lonSqlAccess'}; # remove since sensitive and not needed

# ------------------------------------------------------------- Read hosts file
{
    my $config=IO::File->new("$perlvar{'lonTabDir'}/hosts.tab");

    $total=0;
    while (my $configline=<$config>) {
       $configline=~s/#.*$//;
       unless ($configline=~/\w/) { next; } 
       my ($id,$domain,$role,$name,$ip)=split(/:/,$configline);
       $hostname{$id}=$name;
       $hostdom{$id}=$domain;
       $hostrole{$id}=$role;
       $hostip{$id}=$ip;
       $total++;
       if (($role eq 'library') && ($id ne $perlvar{'lonHostID'})) {
	   $libserv{$id}=$name;
       }
    }
}

print "<h1>Cluster Status ".localtime()."</h1>";
print "<form name='prgstat'>\n".
"<input type='text' name='progress' value='Starting ...' size='100' /><br />".
"</form>\n";;
print "<form name='status' method='post'>\n";
&hidden('refresh',$refresh);

# ==================================================== Main Loop over all Hosts

foreach $local (sort keys %hostname) {
# -- Check general status
    &statuslist($local,'General');
    my %loncron=&replyhash($local,'/lon-status/loncron_simple.txt',1200);
    if (defined($loncron{'local_error'})) {
	$host{$local.'_loncron'}='Could not determine.';
    } else {
	if ((time-$loncron{'time'})>$oneday) {
	    $host{$local.'_loncron'}='Stale.';
	} else {
	}
    }
# -- Check user status
    &statuslist($local,'Users');
    my %userstatus=&replyhash($local,'/cgi-bin/userstatus.pl?simple',600);
    if (defined($userstatus{'local_error'})) {
	$host{$local.'_userstatus'}='Could not determine.';
    } else {
    }
# -- Check mysql status
    &statuslist($local,'Database');
    my %mysql=&replyhash($local,'/lon-status/mysql.txt',1200);
    if (defined($mysql{'local_error'})) {
	$host{$local.'_mysql'}='Could not determine.';
    } else {
	if ((time-$mysql{'time'})>(7*$oneday)) {
	    if ($hostrole{$local} eq 'library') {
		$host{$local.'_mysql'}='Stale.';
		$host{$local.'_mysql_doomed'}=1;
	    }
	    if ($mysql{'mysql'} eq 'defunct') {
		$host{$local.'_mysql'}='Defunct (maybe stale).';
		$host{$local.'_mysql_doomed'}=2;
	    }
	} elsif ($mysql{'mysql'} eq 'defunct') {
	    $host{$local.'_mysql'}='Defunct.';
	    $host{$local.'_mysql_doomed'}=3;
	}
    }
# -- Check rpm status
    &statuslist($local,'RPMs');
    my %checkrpms=&replyhash($local,'/lon-status/checkrpms.txt',2400);
    if (defined($checkrpms{'local_error'})) {
	$host{$local.'_checkrpms'}='Could not determine.';
    } else {
	if ((time-$checkrpms{'time'})>(4*$oneday)) {
	    $host{$local.'_checkrpms'}='Stale.';
	    $host{$local.'_checkrpms_doomed'}=50;
	} elsif ($checkrpms{'status'} eq 'fail') {
	    $host{$local.'_checkrpms'}='Could not checked RPMs.';
	    $host{$local.'_checkrpms_doomed'}=100;
	} elsif ($checkrpms{'rpmcount'}) {
	    $host{$local.'_checkrpms'}='Outdated RPMs: '.
		$checkrpms{'rpmcount'};
	    $host{$local.'_checkrpms_doomed'}=$checkrpms{'rpmcount'};
	}
    }
# -- Check connections
    &statuslist($local,'Connections');
    $host{$local.'_notconnected'}='';
    $host{$local.'_notconnected_doomed'}=0;
    foreach $remote (sort keys %hostname) {
	my $status=&connected($local,$remote);
	$connectionstatus{$local.'_TO_'.$remote}=$status;
	unless (($status eq 'ok') || ($status eq 'not_yet')) {
	    $host{$local.'_notconnected'}.=' '.$remote;
	    $host{$local.'_notconnected_doomed'}++;
	}
    }
# Eventually, use doomed count
    &serverstatus($local);
}

# =============================================================== End Mail Loop
print "</form><script>";
$runtime=time-$starttime;
if ($runtime>=$refresh) {
    print 'document.status.submit();';
} else {
    $refreshtime=int(1000*($refresh-$runtime));
    print "setTimeout('document.status.submit()',$refreshtime);";
}
print "</script></body></html>";
exit 0;
