//! Credential registry trait for looking up authentication data.
use crateProxyError;
use crate;
use crate;
use Future;
/// Trait for retrieving credentials and roles from a backend store.
///
/// Implementations should be cheap to clone (wrap inner state in `Arc`).
///
/// Temporary credentials are resolved via a [`TemporaryCredentialResolver`](crate::auth::TemporaryCredentialResolver)
/// rather than stored here.