With the Call Recording Controls API, it is now possible to record incoming Twilio Programmable Voice calls. Previously, Call Recording needed to be called out in the outgoing call’s API request, or in TwiML, meaning incoming Programmable Voice calls could only be recorded when a <Dial> TwiML command was used. With Call Recording controls, now users can start, pause and resume, and end a call recording - all with a simple API request.
In order to begin recording or modify the recording status, you first need to capture the Twilio Call SID. This is automatically delivered to your webhook as the CallSid parameter value in Twilio’s HTTP request to your webhook. Your webhook will then respond to Twilio with the TwiML for running the incoming call.
Notice: You won’t be able to begin recording the call until Twilio receives and processes your TwiML response. Since your application will receive the Call SID prior to this, it’s possible that an API request to begin recording your call can be submitted too early, resulting in an error. To minimize this possibility, we recommend instituting a delay before submitting your API request, and/or retrying your record requests if they fail.
Begin Recording an In-progress Call
To start recording a live call - either incoming or outgoing - make an HTTP POST request to the call’s Recordings List subresource. Here’s an example cURL script:
curl -XPOST https://api.twilio.com/2010-04-01/Accounts/ACXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/Calls/CAXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX/Recordings.json \ --data-urlencode "RecordingStatusCallback=https://myapp.com/recording-events" \ --data-urlencode "RecordingStatusCallbackEvent=in-progress completed" \ -u "ACXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX:your_auth_token"
This example will begin recording call
CAXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX, and request status updates in your application when the recording begins and ends. To make this script work for you, make the following updates, and then paste it into a terminal window:
- Line 1 update with a valid Account SID and active Call SID
- Line 2 update with your application site for Recording status callbacks (optional)
Note: Recording status callbacks are recommended for gathering the required Call and Recording SIDs for pausing, restarting, and ending active recordings.
- Line 4 update with your Account SID and Auth Token
Additional optional parameters for call recording can be added in your request as well, including dual-channel recording, and silence trimming. For full details on the available recording options, please see Create a Recording Resource (Twilio Docs).