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Raymond_Feng_97's avatar
Raymond_Feng_97
Historic F5 Account
Jul 30, 2012

urgent: need help for regular expression ?

Hi, all

Sorry , I am on site , can anybody help to create one line simple iRule to get the FQDN from the below sip string ?

 

ECSCF-Simulator7.P-LRF.com;lr>

 

Route: ECSCF-Simulator7.P-LRF.com;lr>

 

 

 

Contact: sip.test-site2.ERICSSON2.com:5060>

 

 

 

 

the fqdn is after "sip:" and "@" (if exist") and before ":" or ";"

 

 

 

I want to set the fqdn to one value and do dns query for this domain name , and then change change the destination ip to be that address.

 

 

 

Thanks.

 

 

 

Raymond

 

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5 Replies

  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jul 30, 2012
    Hi Raymond,

     

     

    Can you post the input sample in [ code ] [/ code ] blocks without the spaces?

     

     

    Here's a related post you can reference as well:

     

     

    https://devcentral.f5.com/Forums/tabid/53/aft/60465/Default.aspx60474

     

     

    Thanks, Aaron
  • Raymond_Feng_97's avatar
    Raymond_Feng_97
    Historic F5 Account
    Jul 30, 2012
    
Route:
Contact:

    I want get the FQDN out of the SIP header string , like "sip.test-site2.ERICSSON2.com" and "ECSCF-Simulator7.P-LRF.com" . Thanks.
  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jul 30, 2012
    Can you post a few more examples of the two different header values?

     

     

    Are you able to parse the route and contact headers using separate logic?

     

     

    Here's a first stab at a combined regex that matches the domain of both examples you've shown:

     

     

    (?:(?<=@).*?(?=;|:)|(?<=

     

    Aaron
  • Raymond_Feng_97's avatar
    Raymond_Feng_97
    Historic F5 Account
    Jul 30, 2012
    Sure I can using separate logic for Route and contact , actually my question is focus the FQDN may or may not have "@" . 

     
Contact:
Contact:
Contact:
Contact:

    these is four examples , can I get the sip.test-site2.ericsson2.com with same regex ?

  • hoolio's avatar
    hoolio
    Icon for Cirrostratus rankCirrostratus
    Jul 31, 2012
    The last regex didn't render correctly. And as TCL advanced regexes don't support lookbehinds, the regex won't work. You can do two scan commands for this though: 
    when RULE_INIT {

 Loop through some test strings:
foreach str [list 
{}
{}
{}
{}
{}
{}] {

 Scan assuming a format of