#!/usr/bin/perl # *MUST* have this line above. It won't work with httpd otherwise. # ----------------------------------------------------------------- # Query.cgi # # USAGE: Query.cgi [list] # # $Id: Query.cgi.in.in,v 1.1 2000/02/07 09:48:06 sxw Exp $ # # A perl script to randomly redirect queries to a particular replica # of a broker. HVhttp is a list of known replicas of the broker. # Each replica is represented by the URL of its query page. A replica # is selected at random with precedence given to the local replica. # A redirect to the appropriate query page is returned. If the argument # "list" is present, a list of replicas is returned. # ----------------------------------------------------------------- @HVhttp = ( "/Harvest/brokers/@THIS_BROKER_SHORT_NAME@/query.html" @REPLICAS@ ); $HVname = "@THIS_BROKER_NAME@"; # ----------------------------------------------------------------- # CGIRedir -- Mime content header # ----------------------------------------------------------------- sub CGIRedir { local($url) = @_; print "HTTP/1.0 302 Found\r\n"; print "MIME-Version: 1.0\r\n"; print "Location: $url\r\n"; print "Content-Type: text/html\r\n"; print "\r\n"; } # ----------------------------------------------------------------- # CGIHeader -- Mime content header # ----------------------------------------------------------------- sub CGIHeader { print "HTTP/1.0 200 OK\r\n"; print "MIME-Version: 1.0\r\n"; print "Content-Type: text/html\r\n"; print "Content-Transfer-Encoding: binary\r\n"; print "\r\n"; } # ----------------------------------------------------------------- # HVreplicas -- Display a list of replicas for the user to select. # ----------------------------------------------------------------- sub HVreplicas { local($url); &CGIHeader; $nlocs = $#HVhttp + 1; print STDOUT < $HVname Replicas

$HVname Replicas

This broker is replicated at $nlocs locations. Please choose one from the list below.

EOM foreach $url (@HVhttp) { print "

$url\n"; } print < EOM } # ----------------------------------------------------------------- # main() # ----------------------------------------------------------------- srand(); if (@ARGV[0] eq "list") { &HVreplicas; } elsif ($#HVhttp == 0) { &CGIRedir($HVhttp[0]); } elsif (int(rand(2)) == 0) { &CGIRedir($HVhttp[0]); } else { &CGIRedir($HVhttp[int(rand($#HVhttp + 1))]); } exit 0; # END OF PROGRAM