insert javascript to html pages using irules

Hi Fiko,

Here's an untested example to start with. It requires a blank stream profile and a custom HTTP profile with response chunking set to rechunk be added to the virtual server.

when HTTP_REQUEST {
    Disable stream filter by default
   STREAM::disable
    Don't allow response data to be chunked
   if { [HTTP::version] eq "1.1" } {
       Force downgrade to HTTP 1.0, but still allow keep-alive connections.
       Since HTTP 1.1 is keep-alive by default, and 1.0 isn't,
       we need make sure the headers reflect the keep-alive status. 
      if { [HTTP::header is_keepalive] } {
        HTTP::header replace "Connection" "Keep-Alive"
      }
   }
}
when HTTP_RESPONSE {
   if {[HTTP::header Content-Type] starts_with "text/"} {
       Remove the spaces before and after head in < head >
      STREAM::expression {@< head >@@}
      STREAM::enable
   }
}
when STREAM_MATCHED {
    Once we've hit one match, disable the stream filter for the rest of the response
   STREAM::disable
}
Aaron

See the attached text file for an uncorrupted version.

 

 

Aaron

 

many thanks Aaron, I'll test it out

Hi, I have some concern regarding connection which enter the BIG-IP and trigger the irule

 

 

I'm using variable for the url and in response event will check the url and insert javascript.

 

The problem is when more than one connection occurs at the same time. How the variable will be set?

 

I know there will be time difference even only 0.0001 or so but in this case what if both connection enter virtual server at the same time. Does it will effect the variable set or not?

 

 

i modified the irule into this

 

 

when HTTP_REQUEST {

 

set ::url [HTTP::host][HTTP::uri]

 

}

 

 

when HTTP_RESPONSE {

 

if { $::url equals "192.168.0.202/index.jsp" } {

 

STREAM::expression "change page content here";

 

STREAM::enable;

 

}

 

}

 

 

when STREAM_MATCHED {

 

STREAM::disable

 

}

 

 

or is there any other way to check the url in response without using variables?

 

 

 

 

thanks

From what I understand, that shouldn't be a problem. These devices are designed to handle many concurrent requests. The variable will be set correctly since it's scope is based on the connection.

 

 

http://devcentral.f5.com/Community/GroupDetails/tabid/1082223/asg/50/aft/12361/showtab/groupforums/Default.aspx

As Peter said if you use a local variable you won't have to worry about trampling of variable values between connections. However, you're using $::url which is a global variable. This will get overwritten each time it is set for each connection. You should change $::url to $url to avoid this issue.

 

 

Aaron

Good catch, Aaron. I missed that!