How to replace a HTTP XML POST content with irules?

Hi,

You can use a blank stream profile and the following iRule to replace a string with another string in the HTTP payload of a POST request. You'll need to create a custom HTTP profile with response chunking set to rechunk. You can check the STREAM::expression wiki page (Click here)

Aaron

 
 when HTTP_REQUEST { 
  
     Check if the request is a POST, with a content type of text 
    if {[HTTP::method] eq "POST" && [HTTP::header value Content-Type] contains "text/xml"}{ 
  
        Match the literal string "find" and replace it with "replace" 
       STREAM::expression {@find@replace@}     
  
        Enable the stream filter for this request only 
       STREAM::enable 
  
    } else { 
        Disable the stream filter by default 
       STREAM::disable 
    } 
 }       
 when STREAM_MATCHED {       
     This event is only included for debugging.  You should remove the event after testing is complete.       
    log local0. "[IP::client_addr]:[TCP::local_port]: matched: [STREAM::match]" 
 } 
 

Hi Aaron,

 

 

Thank you for your guidance. Your suggestion is very useful to me. In addition, I just wonder how I can save the seession data for the client.

 

 

In the example below, I would like to reduce the push id length (remove 12345), however, when I return the response to the client I have to keep the the "12345" and attach the "12345" back in the response. How do I use a regular expression to match and save "12345" as a session data, and how could I response back to the client.

 

 

Any idea please let me know.

 

 

Example:

 

 

Client --------(HTTP POST A)---> IRules/F5 -------------(HTTP POST B) ----> Server

 

 

Client <-------(HTTP RES A) -------IRules/F5 <---------- (HTTP RES B) -------- Server

 

 

 

HTTP POST A:

 

DATA

 

 

HTTP RESP A:

 

success

 

 

HTTP POST B:

 

DATA

 

 

 

HTTP RESP B:

 

success

 

 

 

 

 

That should be possible using the STREAM_MATCHED event to modify the stream replacement.

 

 

Is 12345 always the first five characters of the push-id value? Does the format for the string to modify change ever (ie, is it always push-id="value" with the same capitalization and spacing)?

 

 

Thanks,

 

Aaron