[Freeswitch-users] Custom NOTIFY via a proxy

[Neil Burgess]

Hi,

I am trying to send CUSTOM NOTIFY events to devices, using the ESL interface with a PHP script of the following form. I am having partial success, but coming up against problems when using with an outbound proxy:-

       $e = new ESLevent("NOTIFY");
       $e->addHeader("profile", "internal");
	$e->addHeader("from", "1020");
	$e->addHeader("to-uri", "sip:1019 at 192.168.2.3:5063;fs_path=sip:82.24.214.226:5063");
	$e->addHeader("from-uri", "sip:1020 at pbx.rm.com");
	$e->addHeader("host", "pbx.rm.com");
	$e->addHeader("event-string", "check-sync");
	$e->addHeader("content-type", "application/simple-message-summary");
	$e->addBody("ok");
	$res = $sockFSServerCommand->sendEvent($e);

In our setup, we have several FreeSwitch boxes sitting behind two OpenSIPS load balancers. These Load Balancers handle registrations, etc. When we originate calls from FreeSwitch, we use an originate URL of the form (sofia/internal/1001 at sip.redmatter.com;fs_path=sip:84.45.30.2),  and use fs_path to push the call via the right load balancer. This works perfectly.
 
So, with the custom NOTIFY's I also need to make them follow the same path. As mentioned, we already have the contact string in our hand from the OpenSIPS registration server, but can't see how I can use that plus force the outbound path for the Notify. Was thinking I could use fs_path in the uri (as above) but doesn't seem to work, i.e. the wrong IP is used, and NOTIFY is messed up somewhat! Maybe another combination I am missing! Example packet capture follows:

NOTIFY sip:1019 at 192.168.2.3:5063;fs_path=sip:82.24.214.22:5063 SIP/2.0
Via: SIP/2.0/UDP 212.85.24.245;rport;branch=z9hG4bKv268QHcy539yc
Max-Forwards: 70
From: <sip:1020 at pbx.rm.com>;tag=0rer8BS2etmmc
To: <sip:1019 at 192.168.2.3:5063>;fs_path=sip:82.24.214.22:5063
Call-ID: 5a08d5c6-1a8e-122e-3885-0024e86c401a
CSeq: 134921 NOTIFY
Contact: <sip:mod_sofia at 212.85.24.245:5060>
User-Agent: FreeSWITCH-mod_sofia/1.0.5-20100211-0400-16602
Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, MESSAGE, UPDATE, INFO, REGISTER, REFER, NOTIFY, PUBLISH, SUBSCRIBE
Supported: precondition, path, replaces
Event: check-sync
Allow-Events: talk, presence, dialog, line-seize, call-info, sla, include-session-description, presence.winfo, message-summary, refer
Subscription-State: terminated;reason=timeout
Content-Type: application/simple-message-summary
Content-Length: 2

ok

Any thoughts gratefully appreciated.

Rgds,
Neil