Set Manual Cookie Peristence

when RULE_INIT {
set static::cookie_name "my_node_forced"
}
when HTTP_REQUEST {
 Get node id from URL ending in ?node=server1, ?node=server2, etc.
set node_forced [findstr [HTTP::query] "node=" 5]

 Or from previous cookie
set has_cookie [HTTP::cookie exists $static::cookie_name]

 If node_forced (from query) isn't there but cookie exists - set node_forced = cookie value
if { $node_forced eq "" and $has_cookie } {
set node_forced [HTTP::cookie value $static::cookie_name]
}

 If node_forced (from query) is there but cookie is not - set cookie flag
if { $node_forced ne "" and !$has_cookie } {
set do_cookie 1
}

 Map node id to IP and port found in a class
if { $node_forced ne "" } {
set node_data [class match -value $node_forced equals my_forced_nodes]
if { $node_data ne "" } {
set node_ip [getfield $node_data " " 1]
set node_port [getfield $node_data " " 2]
pool local-pool member $node_ip $node_port
} 
} 
}
when HTTP_RESPONSE {
if { [info exists do_cookie] } {
unset do_cookie
 Add a cookie to continue forcing node assignment
HTTP::cookie insert name $static::cookie_name value $node_forced path "/"
} 
}