type Authorizer interface { Authorize(req *http.Request, resource string, action Action) error }
type AuthClient interface { Authenticate(username, password string) (string, error) }In summary, the `github.com.juju.juju.apiserver.common` package in Go provides interfaces and functions for authentication, authorization, and access control in Juju API Server. The `Authorizer` interface defines a method to authorize requests while the `AuthClient` interface provides a method for client authentication.