How to catch the end of a call optimally?

Question

Asterisk

Hello! Installed Asterisk (Asterisk 13.18.3~dfsg-1ubuntu4 built by nobody @ buildd.debian.org on a unknown running Linux) on a VPS (Ubuntu 18.04.1 LTS (GNU/Linux 4.15.0-46-generic x86_64)). An outgoing call is made using the call file. It has a variable (the value in each file is unique) set via Set (Set: code=123). If the subscriber did not pick up the phone or for some reason we could not get through to the subscriber, then it is necessary to send a GET request to the URL with the code parameter (which corresponds to this call). How to catch the end of the call and implement it?
Willing to provide additional information. I will be glad for any help!

Answer 1

After the desired Dial, as well as in the h extension of the dialplan context section you need, make a call to a certain context through gosub.
In this context, check that the billsec CDR variable is missing or less than, for example, 5 seconds, and send your request through the CURL aster function