[sr-dev] AVPs in replies?

[Andrei Pelinescu-Onciul]

On Dec 10, 2009 at 10:45, Juha Heinanen <jh at tutpro.com> wrote:
> Klaus Darilion writes:
>  > Juha Heinanen wrote:
>  > > Andrei Pelinescu-Onciul writes:
>  > > 
>  > >  > > K's tm module can be configured to have transaction AVPs or message AVPs:
>  > >  > > http://kamailio.org/docs/modules/1.5.x/tm#id2530480
>  > >  > > 
>  > >  > > What is the behaviour of ser's tm module? I need AVPs in reply route - 
>  > >  > > is it supported?
>  > >  > 
>  > >  > In theory, yes by default. In practice it looks like there's a bug if
>  > >  > several replies are processed in the same time.
>  > >  > As a quick fix for sr_3.0 I might introduce the same mechanism as in k.
>  > > 
>  > > i didn't quite get this.  in sr_3.0, i do see avps in onrely_route that
>  > > were set in route block before t_relay was called.  is this what andrei
>  > > means in above by default behavior?  if so that is fine with me.
>  > 
>  > Yes. So sr has a different default behavior than k. (should be 
>  > documented in migration guide)
> 
> what is the conclusion about this?

I'll have a quick fix in the next few days (similar to k, but I'm
thinking of going for read-only avps by default and a modparam to turn
them r/w at the price of locking the reply route). In the long run
we need a better fix.
> 
> it is ok with me if in in sr_3.0 onreply_avp_mode is on by default
> (and even on always), but i'm very worried, if it does not work when
> several replies are processed simultaneously.

Yes, if avps are written in the onreply_route and replies for the same
transaction are processed in parallel there's the chance of corrupting
the transaction avp list or even crashing.

Andrei