LAML call updating demo
In this example, we are going to receive a call via LAML, have it paused in a sound loop, then update it with a destination and check the new target gets called.
The goal is to demonstrate a mechanism that could be used, for example, to wait for a mobile SIP endpoint to be registered before bridging the call.
Usage
First of all, copy the env.example file into .env and adjust the values using your SignalWire project credentials.
Start the application with dotenv ruby main.rb.
Set up a number or SIP domain app to point at APP_URL/receive.
Call the number and listen to a bit of cool jazz.
Go to APP_URL then click on the call SID of the call you want to redirect.
The APP_CALL_DESTINATION will be dialed.
API interactions
The inbound call is held in a looping pattern with a simple LAML document similar to the following:
<?xml version="1.0" encoding="UTF-8"?>
<Response>
<Play loop="0">https://your-application.com/audio.mp3</Play>
</Response>
The call SID has to be saved somehow by the server generating the LAML.
That call SID is referenced in a REST API request that replaces the existing document with a new one:
curl https://example.signalwire.com/api/laml/2010-04-01/Accounts/{AccountSid}/Calls/{Sid}.json \
-X POST \
--data-urlencode "url=https://your-new-lamrl-url.com" \
--data-urlencode "fallbackUrl=https://your-new-lamrl-url.com" \
-u "YourProjectID:YourAuthToken"
The URL you pass in in the above request will be sending the call to the final destination:
<?xml version="1.0" encoding="UTF-8"?>
<Response>
<Dial>
<Sip>sip:alice@example.com</Sip>
</Dial>
</Response>