18 Nov
2013
18 Nov
'13
6:16 p.m.
On 18 Nov 2013, at 15:45, Alex Balashov <abalashov(a)evaristesys.com> wrote:
Hi Victor,
Pretty much all HTTP calls, no matter how you architect them, block Kamailio SIP worker
threads. There is a low practical limit to the number of of SIP worker threads you can
have, so this can lead to SIP messages being dropped and sluggish response time very
quickly.
The json-rpc module has what I believe is an asynch http call, returning in
another route block.
I've mailed earlier about all our HTTP clients. There's a mess that needs someone
to clean out.
/O
The exec_avp() function has this liability, as does the http_query()[1] function in the
'utils' module, although the http_query() function does have a timeout
parameter[2] that works, so if a short timeout satisfies you, this is a superior
alternative to exec_avp().
However, to architect this in a truly asynchronous way, you're either going to have
to query the thing you want via SIP (i.e. to a SIP redirect server) itself, or use some of
the newer asynchronous/deferred processing features that are already in place[3], or being
pushed into the 4.1 branch nowadays. Both options certainly incur greater complexity than
using http_query(), so if the fact that it has a working timeout setting satisfies you,
just use that.
-- Alex
[1] http://kamailio.org/docs/modules/4.0.x/modules/utils.html#idm1336
[2] http://kamailio.org/docs/modules/4.0.x/modules/utils.html#idp2631720
[3] http://kamailio.org/docs/modules/devel/modules/async.html
http://kamailio.org/docs/modules/4.1.x/modules/tmx.html#idp15326008
On 11/18/2013 09:39 AM, Victor Torre Antunez wrote:
Hi all,
I´m using EXEC Module to execute a HTTP request via curl, to comunicate
with another app like this:
exec_avp("curl --connect-timeout 1 --max-time 2
http://IP_ADDR:PORT/PATH/'$fU'/'$tU'/'$hdr(Call-ID)'…'$hdr(Call-ID)'",
"$avp(s:output)");
Sometimes Kamailio blocks when HTTP server does not response in time,
despite the max-time parameter.
I found this know issue on EXEC module docs:
"There is currently no guarantee that scripts ever return and stop
blocking SIP server. (There is kill.c but it is not used along with the
current mechanisms based on popen. Besides that kill.c is ugly)."
Does anyone know a better way to communicate Kamailio with a HTTP server
without blocks? I will try a python script to send the HTTP request and
call it with APP_PYTHON module. Has anyone had blocks with APP_PYTHON
module?
Thanks in advance.
--
*Victor*
_______________________________________________
SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
sr-users(a)lists.sip-router.org
http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
--
Alex Balashov - Principal
Evariste Systems LLC
235 E Ponce de Leon Ave
Suite 106
Decatur, GA 30030
United States
Tel: +1-678-954-0670
Web: http://www.evaristesys.com/, http://www.alexbalashov.com/
_______________________________________________
SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
sr-users(a)lists.sip-router.org
http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users