( SSL/TLS, Token-based authentication with Google) • But I think this is not for application level authentication. (this is a gRPC connection or channel authentication.) • We can use Metadata for application level authentication.
use gRPC directly on browser. ※ grpc-web provides client and proxy server implementation for running gRPC on browser (gRPC-Web protocol is a cutting-edge spec that enables invoking gRPC services from modern browsers.). • Also, we have to support internal legacy services using REST. • We can use grpc-gateway for REST Client.