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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.
1 Reply
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
