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Emre_27149's avatar
Emre_27149
Icon for Nimbostratus rankNimbostratus
May 03, 2011

disable ram cache while when get http error codes

Hi All,

I have the below irule code but I also want to disable the ram cache feature when a backend server returned a http error codes (404, 303... ) to clients.So how can I need to update the rule to accomplish my goal.?

 

Thank you,

 

 

 

rule cache_rule3 {

 

when HTTP_REQUEST {

 

if { [ class match [HTTP::path] starts_with cache_obj] } {

 

CACHE::enable

 

log local0. "Caching [HTTP::path]"

 

} else {

 

log local0. "NON Caching [HTTP::path]"

 

CACHE::disable

 

log local0. "Non Caching [HTTP::path]"

 

}

 

}

 

application delivery
dev
devops
iRules
  • hooleylist's avatar
    hooleylist
    Icon for Cirrostratus rankCirrostratus
    May 03, 2011
    Hi Emre,

     

     

    Here's an option:

     

     

    when HTTP_REQUEST {

   set uri [HTTP::uri]

   if { [ class match [HTTP::path] starts_with cache_obj] } {

      CACHE::enable
      log local0. "Caching [HTTP::path]"

   } else {

      log local0. "NON Caching [HTTP::path]"
      CACHE::disable
   }
}
when HTTP_RESPONSE {

    Check the response status code
   switch [HTTP::status] {

      404 -
      500 -
      503 {
         CACHE::disable
         log local0. "Disabled cache for [HTTP::status] response to $uri"
      }
      default {
         CACHE::enable
         log local0. "Enabled cache for [HTTP::status] response to $uri"
      }
   }
}

     

     

    If you wanted to enable caching only for 200, 301, 302, etc responses, you could flip the CACHE::enable/disable statements:

     

     

    when HTTP_REQUEST {

   set uri [HTTP::uri]

   if { [ class match [HTTP::path] starts_with cache_obj] } {

      CACHE::enable
      log local0. "Caching [HTTP::path]"

   } else {

      log local0. "NON Caching [HTTP::path]"
      CACHE::disable
   }
}
when HTTP_RESPONSE {

    Check the response status code
   switch [HTTP::status] {

      200 -
      301 -
      302 {
         CACHE::enable
         log local0. "Enabled cache for [HTTP::status] response to $uri"
      }
      default {
         CACHE::disable
         log local0. "Disabled cache for [HTTP::status] response to $uri"
      }
   }
}

     

     

    Aaron
  • Emre_27149's avatar
    Emre_27149
    Icon for Nimbostratus rankNimbostratus
    May 03, 2011

    Hi Aaron,

     

    Thank you so much for your interest and quick response.

     

    Kindly..

     

  • Scott_Hopkins's avatar
    Scott_Hopkins
    Icon for Nimbostratus rankNimbostratus
    Nov 15, 2013

    I know this is digging up a really old post, but one caveat on hoolio's second recommendation:

     

    If you wanted to enable caching only for 200, 301, 302, etc responses, you could flip the CACHE::enable/disable statements:

     

    > when HTTP_REQUEST {
> 
>    set uri [HTTP::uri]
> 
>    if { [ class match [HTTP::path] starts_with cache_obj] } {
> 
>       CACHE::enable
>       log local0. "Caching [HTTP::path]"
> 
>    } else {
> 
>       log local0. "NON Caching [HTTP::path]"
>       CACHE::disable
>    }
> }
> when HTTP_RESPONSE {
> 
>     Check the response status code
>    switch [HTTP::status] {
> 
>       200 -
>       301 -
>       302 {
>          CACHE::enable
>          log local0. "Enabled cache for [HTTP::status] response to $uri"
>       }
>       default {
>          CACHE::disable
>          log local0. "Disabled cache for [HTTP::status] response to $uri"
>       }
>    }
> }

    Without 304 in the 'CACHE::enable' half of the switch statement in the HTTP_RESPONSE event, RAMCache doesn't properly catch responses from the originating web server on checks for expired objects (at least on 10.2.4 HF3).