when HTTP_REQUEST {
       
if {[HTTP::method] eq "GET" and [HTTP::uri] eq "/"}{   
 set expire_content_timeout 300       
  } else {     
set expire_content_timeout [findclass [string tolower [string range [HTTP::path] [string last . [HTTP::path]] end]] $::class_cacheable_file_types " "] 
log local0.debug "$expire_content_timeout"  
#log local0.debug "[string tolower [string range [HTTP::path] [string last . [HTTP::path]] end]]"
  }      }    
    when HTTP_RESPONSE {      
   if { $expire_content_timeout ne "" } {    
        HTTP::header replace "Cache-Control" "max-age=$expire_content_timeout, public"      
   HTTP::header replace "Expires" "[clock format [expr ([clock seconds]+$expire_content_timeout)] -format "%a, %d %h %Y %T GMT" -gmt true]"     
    } else {       
     #HTTP::header replace "Cache-Control" "private"     
           HTTP::header replace Expires {-1}     
        }    
  }