Smartest way to do a class lookup case insensitive

Question

Hi,&nbsp;
 &nbsp;
Everything is in the title.&nbsp;
 &nbsp;
I'd like to use class lookup (or a class match -value as it's the same) in a case insenstive way. There isn't any "-nocase" option like in some other class commands.&nbsp;
 &nbsp;
Basically, I have a datagroup for URL redirections (many "http://www.a.com/b" := "http://www.c.com/d") and I want the URL redirections to be case insensitive.&nbsp;
 &nbsp;
Thanks!&nbsp;

what_lies_bene1 · Answer

You'll want to use the stringtolower command, more info here: https://devcentral.f5.com/tutorials/tech-tips/irules-101-13-tcl-string-commands-part-1

nitass · Answer

e.g. 
  
 [root@ve10:Active] config  b virtual bar list
virtual bar {
   snat automap
   pool foo
   destination 172.28.19.79:80
   ip protocol 6
   rules myrule
   profiles {
      http {}
      tcp {}
   }
}
[root@ve10:Active] config  b rule myrule list
rule myrule {
   when HTTP_REQUEST {
   set host [HTTP::host]
   set uri [HTTP::uri]
   if { [class match -- "http://[string tolower $host$uri]" equals redirection_class] } {
      HTTP::redirect [class match -value "http://[string tolower $host$uri]" equals redirection_class]
   }
}
}
[root@ve10:Active] config  b class redirection_class list
class redirection_class {
   "http://www.a.com/b" { "http://www.c.com/d" }
}

[root@ve10:Active] config  curl -I http://172.28.19.79/b -H "Host: www.a.com"
HTTP/1.0 302 Found
Location: http://www.c.com/d
Server: BigIP
Connection: Keep-Alive
Content-Length: 0

[root@ve10:Active] config  curl -I http://172.28.19.79/B -H "Host: www.A.com"
HTTP/1.0 302 Found
Location: http://www.c.com/d
Server: BigIP
Connection: Keep-Alive
Content-Length: 0

nitass · Answer

i think this could be a bit better. 
  
 when HTTP_REQUEST {
   set host [string tolower [HTTP::host]]
   set uri [string tolower [HTTP::uri]]
   if { [class match -- "http://$host$uri" equals redirection_class] } {
      HTTP::redirect [class match -value "http://$host$uri" equals redirection_class]
   }
}

csa · Answer

Thanks all for your answers. 
&nbsp;  
&nbsp; I know the "string tolower" function, but I think your solutions have the same issue as mine: you must write the lowcase URL in the data group. 
&nbsp;  
&nbsp; My idea would be to compare the values whatever the case is in my data group. I have regularly requests to implement redirections for long URLs, I'd like to avoid switching them to lowercase before putting them in the data group. 
&nbsp;  &nbsp;

hoolio · Answer

If you can't/don't want to guarantee that the data group entries are in lower case, you could loop through each data group element name and set it to lowercase for comparison or use string match -nocase.  However, the overhead for the looping should be higher than using a native class command with string tolower on the input string. 
&nbsp;  
&nbsp; Aaron

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Smartest way to do a class lookup case insensitive

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