I'm working on connecting Nest and SmartThings and I'm running into an issue with the redirect url for auth. SmartThings requires a redirect url that will be different for every user. But it appears the Nest API will only redirect back to exactly the URL provided in client settings. Am I missing something? I would rather not use pin auth as forcing users to remember the pin isn't ideal.
Nest does not support wildcard redirect URI's. It is expected that you run your own server to capture the response. (Which can then redirect to user or device specific services as needed)
The PIN flow only requires the user to enter the PIN number only once to pair, after that the client app can generate a token that is good for the life of that app. (For all practical purposes)