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Forum Discussion

Nik's avatar
Nik
Icon for Cirrus rankCirrus
Jan 06, 2011

stream find/replace expression with an exclude - take 2

inserting base href code into a post breaks the whole page.. so here we go again with psudo html:

 

 

--

 

 

 

the problem is i'm breaking internet explorer compatibility with a find/replace that i'm doing. here's a more specific example. again, three different strings:

 

 

 

[base href="http://www.domain.com/" /]

 

 

 

[a href="http://www.domain.com/path/to/file.jpg width="123" height="456" /]

 

 

 

[a href=http://www.domain.com/file/without/quotes.html /]

 

 

 

now, if i do something like this, it replaces all three domain names with "/" however i only want to replace the second two, not the first since it breaks compatibility with internet explorer:

 

 

 

STREAM::expression {@http://forexforums.dailyfx.com/@/@}

 

 

 

using stream_matched might do the job, i was hoping there'd be something a little simpler though.

 

 

 

thanks.

 

 

application delivery
dev
devops
iRules

3 Replies

  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jan 06, 2011
    I think this might work, if you only want to rewrite a href's: 

    
when HTTP_REQUEST {
    Disable the stream filter for all requests
   STREAM::disable
}
when HTTP_RESPONSE {  

    Check if response type is text  
   if {[HTTP::header value Content-Type] contains "text"}{  

       Match a tags for http://www.domain.com/
      STREAM::expression {@
  • Nik's avatar
    Nik
    Icon for Cirrus rankCirrus
    Jan 06, 2011
    it would be things like img and embed also, i just want to exclude base href.

     

     

    that does seem like a good solution though.
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jan 06, 2011
    You could make the regex more general and then check that STREAM::match in STREAM_MATCHED doesn't contain "< base href" before doing the replacement. This would match < followed by any number of chars that aren't a > followed by http://www.domain.com/:

    STREAM::expression {@<[^>]*?http://www.domain.com/@@}

    Aaron