[SR-Users] Is there any globle variable/flag mechanism in Kamailio

[Alex Balashov]

On 04/12/2011 01:54 PM, Derrick Ding wrote:

> I wonder if there's any other mechanism that I can use to record the
> state and can be used as flag.

That is because a stateful proxy is, by default, transaction-stateful. 
A "call" is a dialog, which consists of several transactions.  Proxies 
are not, by default, dialog-stateful.  It sounds like you're looking for 
something that can persist throughout the lifetime of a dialog.

Fortunately, Kamailio does have a 'dialog' module that adds this 
functionality.  The doc page for the module is here:

   http://www.kamailio.org/docs/modules/3.1.x/modules_k/dialog.html

If you set a dialog to be tracked using the 'dialog' module, you can use 
so-called dialog flags:

 
http://www.kamailio.org/docs/modules/3.1.x/modules_k/dialog.html#id2965748

 
http://www.kamailio.org/docs/modules/3.1.x/modules_k/dialog.html#id2965808

These will be valid for the life of a dialog.

Another option--which also has the effect of being dialog-persistent, 
but does not involve use of the dialog module--is to stow something in a 
Record-Route header value, which I assume your proxy is adding:

   http://www.kamailio.org/docs/modules/3.1.x/modules_k/rr.html#id2663290
 
http://www.kamailio.org/docs/modules/3.1.x/modules_k/rr.html#check-route-param-id

-- Alex

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Alex Balashov - Principal
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