Conditional stream rewrite based on requested uri

Hi Joe,

That looks good. With TCL, you need to escape hyphens in variable names with curly braces: ${requested-uri}. It's easier to use an underscore instead.

Here is an updated version you can try:

 
 when HTTP_REQUEST { 
   switch -glob [string tolower [HTTP::uri]] { 
     /uri1* - 
     /uri2* { 
       set check_response 0 
       snatpool SNAT_DMZ 
       pool pool_www.mysite.org_URI1 
     } 
     /testlink* { 
       snatpool SNAT_APZ 
       set check_response 1 
       pool pool_www.mysite.org_TESTLINK 
     } 
   } 
 } 
 when HTTP_RESPONSE { 
   if {$check_response} { 
     STREAM::expression "@http://www.mysite.org@https://www.mysite.org@" 
     STREAM::enable 
   } else { 
     STREAM::disable 
   } 
 } 
 

Aaron

Aaron,

Thanks again for your help! In your updated rule you used "set check_response 0" and "set check_response 1". This works if there are only two cases. I had actually truncated my irule a bit and there are actually several switch cases. I suppose I could just set check_response to 1 for each uri I wanted to use the stream expression for? Assuming I wanted to use the same stream expression for all match cases.

What if I wanted to use a different stream expression for each uri? Could I set check_response to 1, 2, 3, respectively, and then do a

 
 switch $check_response { 
    1 { 
    STREAM::expression "@http://host1@https://host1@"  
    STREAM::enable 
    } 
    2 { 
    STREAM::expression "@http://host2@https://host2@"  
    STREAM::enable 
    } 
    3 { 
    STREAM::expression "@http://host3@https://host3@"  
    STREAM::enable 
    } default { 
    STREAM::disable 
    } 
 }    
 

Also, rather than use 1, 2, 3, I could use something more intuitive that matches the path like uri1, uri2, uri3. This doesn't necessarily apply to this scenario but I have needed/wanted to do this type of thing before and just didn't know how.

Thanks,

Joe

Hi Joe,

That looks like it would work. You could save a bit on the switch evaluation by setting the stream expression in a variable in HTTP_REQUEST for cases you want to use a stream profile for (and unsetting it by default on each request):

 
 when HTTP_REQUEST { 
  
    Unset the stream_expr variable if it exists already 
   if {[info exists stream_expr]}{ unset stream_expr } 
  
    Check the requested URI 
   switch -glob [string tolower [HTTP::uri]] { 
     /uri1* - 
     /uri2* { 
       set stream_expr "@http://www.mysite.org@https://www.mysite.org@" 
       snatpool SNAT_DMZ 
       pool pool_www.mysite.org_URI1 
     } 
     /uri3* - 
     /uri4* { 
       set stream_expr "@http://www.mysite4.org@https://www.mysite4.org@" 
       snatpool SNAT_DMZ 
       pool pool_www.mysite.org_URI4 
     } 
     /uri5* - 
     /uri6* { 
       snatpool SNAT_DMZ 
       pool pool_www.mysite.org_URI4 
     } 
     /testlink* { 
       set stream_expr "@http://www.mysite.test.org@https://www.mysite.test.org@" 
       snatpool SNAT_APZ 
       pool pool_www.mysite.org_TESTLINK 
     } 
   } 
 } 
 when HTTP_RESPONSE { 
   if {[info exists stream_expr]} { 
     STREAM::expression $stream_expr 
     STREAM::enable 
   } else { 
     STREAM::disable 
   } 
 } 
 

Aaron

Beautiful!! Does that qualify as a Nerd Alert if I think an iRule is beautiful?? Thanks a ton!