while ( my $q = new CGI::Fast ) {
    my $query = $q->param('node');
    print "Content-type: text/plain\n\n";
    ++$n;
    print "You are request number $n. Have a good day!\n";
    print "query: $query\n";
    $nodes{ exists $nodes{$query} ? $query : '_err' }();
    print "done!\n";
}