iRule – Persistence Across HTTP Method


when HTTP_REQUEST {
set HOST [string tolower [HTTP::host]]

#Persistence is enabled for specific domain
if { $HOST equals "domain.com" }{

#Persistence for GET Request
if { [HTTP::method] equals "GET" } {
set SESSIONID [findstr [HTTP::uri] "uuid=" 5 20]
set KEY [crc32 $HOST$SESSIONID]

persist hash $KEY 30

#Collect Data upto Content Length or 1048
} elseif { (([HTTP::method] equals "POST") and ([HTTP::uri] contains "/ptm/tentxml.jsp")) } {

if {[HTTP::header "Content-Length"] ne "" && [HTTP::header "Content-Length"] <= 1048 } {
HTTP::collect $CONTENT
}
}
}

}

#Persist based on information available in the POST data
when HTTP_REQUEST_DATA {
if { (([HTTP::method] equals "POST") and ([HTTP::uri] contains "/ptm/tentxml.jsp")) } {

set HOST [string tolower [HTTP::host]]
set SESSIONID [findstr [HTTP::payload] "uuid=" 5 20]
set KEY [crc32 $HOST$SESSIONID]

persist hash $KEY 30
}
}

In the above iRule, persistence is maintained across HTTP GET & POST Methods. The Session id is present within:

URI of GET Request

POST Data

Persistence key is a combination of the domain & session id – set KEY [crc32 $HOST$SESSIONID]

In order to identify the Session id within the POST data, we will be collecting the data of size defined by the “Content-Length” header or default of 1048 bytes.

The iRULE would have to be utilized within an UIE persistence profile with “Match Across Services” for persistence across HTTP & HTTPS Virtual Servers.

 

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