get https://api.sonos.com/login/v3/oauth
Use the Create Authorization Code API to send a user to the Sonos login service, for example, with a button instructing the user to enable your integration to use Sonos that sends the user to your redirect URI.
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Sonos</title>
</head>
<body data-init="" data-bright-tag="false">
<button
onclick="location.href='https://api.sonos.com/login/v3/oauth?client_id={YOUR CLIENT KEY}&response_type=code&state={TESTSTATE}&scope=playback-control-all&redirect_uri=https%3A%2F%2Facme.example.com%2Flogin'"
type="button">
Sign in with Sonos
</button>
</body>
</html>