In this example https://aws.amazon.com/ru/blogs/business-productivity/how-to-enable-client-side-recording-using-the-amazon-chime-sdk/ they recording video using ECS. I don't understand where i find meetingUrl. And the main question: can i record video from chime inside serverless lambda?
Lambda was not used in first place for this solution because of its timeout limit of 15 minutes. If this is not an issue for you, you may change the solution to use it for Lambda.
I have personally used ffmpeg library inside Lambda and you can find online help for that.
There's a note on meetingUrl in the demo's github documentation.