Forum Discussion
vivek_76299
Nimbostratus
Nimbostratushow to extracting part of a header
Hi All,
There is a HTTP header "ROUTE=Poison^Abb^POISON007;TCS^Abb^CL02;Virtual^Abb^VPOOL1" or "ROUTE=TLL^Add^CL02;Virtual^Abb^VPOOL2". How can i extract the "Virtual^Abb^XXXXX" from the header. I read that substr is not recommended to use with the optional 3rd parameter. Please let me know the how the above value can be obtained in an iRule.
hoolioCirrostratus
If there are arbitrary numbers of fields in between the ^'s, most string/scan operations wouldn't work. Is there a pattern that you want to parse the two fields between the carets after Virtual^?
getfield would work to split the string on the string ;virtual^. You could then break up the last half on the ^. Here's an untested snippet:
set tmp [getfield [HTTP::header route] {;virtual^} 2]
log local0. "Parsed [HTTP::header route] to $tmp"
scan $tmp {^%[^^]^%[^^]} a b
log local0. "Parsed $tmp to $a and $b"
If that works, you can skip the intermediate variable:
scan [getfield [HTTP::header route] {;virtual^} 2] {^%[^^]^%[^^]} a b
log local0. "Parsed [HTTP::header route] to $a and $b"
Aaron