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Forum Discussion

jquinones82_469's avatar
jquinones82_469
Icon for Nimbostratus rankNimbostratus
Oct 20, 2010

how do you check for a null http referer

I want to check for a blank http referer for an IRULE     ([HTTP::header "Referer"] equals $null)     is there some type of variable or way to check for this?     Would I have to use...
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hoolio's avatar
hoolio
Icon for Cirrostratus rankCirrostratus
Oct 20, 2010
I think [HTTP::header $header_name] will return a null string even if the header doesn't exist, so you could combine that with a check to see if the header exists:

 

 

if {[HTTP::header exists Referer] && [HTTP::header Referer] eq ""}{

 

 

Or if you just want to check that it's not null you could use:

 

 

if {[HTTP::header Referer] ne ""}{

 

 

Aaron