Disallow multiple types via navigator.credentials's methods #244
Description
Moving discussion from w3c-fedid/digital-credentials#140 to here....
As spec'ed, the current API allows calling the methods on CredentialsContainer with multiple request types. However, in practice, this doesn't quite work because some of the methods show quite complicated UIs. Additionally, as this capability is not something that's been implemented by anyone (AFAIK), we should consider not allowing that.
Thus, the proposal is to check if more than one credential request (and creation?) option has been passed, and if so, throw a NotAllowedError.
To be clear:
// Throws a NotSupportedError
await navigator.credentials.get({
digital: ...,
publicKey: ...,
federated: ...,
});