On Wed, May 12, 2010 at 11:59 AM, Neil Patel <neilp@cs.stanford.edu> wrote:
Thanks for the tips.

Where are there examples of using ESL to register and handle events? For e.g. I don't see any example of how to register for a change in channel variable endpoint_disposition. Or even to check the CHANNEL_STATE event.

-Neil

Neil,

Check out the event socket documentation, specifically the "events plain all" and "filter" commands. You can listen to all events or just specific ones:
http://wiki.freeswitch.org/wiki/Event_socket

If you want to experiment with the event socket and the various events then use fs_cli. Connect with fs_cli and then issue "/log 0" which turns off all debug messages. Now you have basically a raw event socket. Try some of these commands:

/event plain all

watch the fun messages fly. :)

You can filter them as well:

/filter Event-Name CHANNEL_STATE
/filter Event-Name CHANNEL_HANGUP

when you apply a filter you will receive only those things you choose. A it's a "filter in" not filter out. Another way of saying it is "show me events named CHANNEL_STATE" and "show me events named CHANNEL_HANGUP"

just note that in your script you will be using the ESL abstractions for these:

http://wiki.freeswitch.org/wiki/Esl#ESLconnection_Object

I hope that helps! Have fun.
-MC