[OpenSIPS-Devel] issue of get_redirects, serialize_branches and next_branche for rediect call scenarios

[Răzvan Crainea]

Hi, Di-Shi!

I don't think serialize_branches should still set the AVP, because it 
will basically be a no-op. However, your logic is OK, and I agree this 
is somehow hard to follow. But review-ing the code, I don't see why it 
wouldn't work as it is... Are there any issues with the snippet below? 
Because I think it should work just fine.

Best regards,
Răzvan

On 04/23/2018 06:03 PM, Di-Shi Sun via Devel wrote:
> All,
> 
> We are testing OpenSIPS for simple redirect call scenarios. We expect 
> OpenSIPS to try all Contact headers in the SIP 3xx respectively based on 
> q value. For the SIP 3xx with multiple Contact headers, our 
> configuration works fine. But for the SIP 3xx with one Contact header, 
> it does not work.
> 
> Configuration:
> 
> failure_route[1] {
> 
>    if (t_check_status("3[0-9][0-9]")) {
> 
>      get_redirects("*");
> 
>      serialize_branches(1);
> 
>      next_branches();
> 
>      t_relay();
> 
>    }
> 
> }
> 
>  From OpenSIPS source code, we know that
> 
> 1.            get_redirects puts the 1st Contact header URI into RURI, 
> puts the 2nd Contact header URI into the 1st branch, etc.
> 
> 2.            serialize_branches sorts RURI and all branches, and puts 
> them in a AVP.
> 
> 3.            next_branches extracts next hop from the AVP.
> 
> When there are multiple Contact headers, all (get_redirects, 
> serialize_branches and next_branch) work fine. When there is only one 
> Contact header, get_redirects still works fine. But since there is not 
> branch, serialize_branches does nothing especially does not set the AVP, 
> then next_branches does nothing too since the AVP is empty.
> 
> The questions are,
> 
> 1.            Should serialize_branches still set the AVP when there is 
> one Contact header?
> 
> 2.            According the comments for next_branches, in failure 
> route, all Contact headers should be mapped to branches. Then, is the 
> behavior of get_redirects, which can only be called in failure route 
> block, correct?
> 
> If these are the designed behaviors, we can live on it. It is easy to 
> write a working configuration.
> 
> Thanks,
> 
> Di-Shi Sun
> 
> VoIP Routing, Accounting, Security
> 
> www.TransNexus.com <http://www.transnexus.com/>
> 
> 
> 
> _______________________________________________
> Devel mailing list
> Devel at lists.opensips.org
> http://lists.opensips.org/cgi-bin/mailman/listinfo/devel
> 

-- 
Răzvan Crainea
OpenSIPS Core Developer
   http://www.opensips-solutions.com
OpenSIPS Summit 2018
   http://www.opensips.org/events/Summit-2018Amsterdam