Lambda function which toggles the play/pause state of a Sonos system.
For instructions, see: https://www.david-merrick.com/2017/05/16/using-an-aws-iot-button-to-control-sonos-speakers/
The AWS IoT button triggers a Lambda function, which talks to a Sonos API server running on a Raspberry Pi. This server is deployed with Resin.io so that I could give it a public web address without having to deal with NAT traversal/port forwarding.