public RestChannel(RestServiceCollection serviceCollection, string endpoint, ChannelCredentials credentials, GrpcChannelOptions options) : base(endpoint)
        {
            _serviceCollection = serviceCollection;

            // Reuse a single CallInvoker however many times CreateCallInvoker is called.
            _callInvoker = new RestCallInvoker(this);
            // TODO: Handle endpoints better...

            // TODO: Avoid creating an HTTP Client for every channel?
            _httpClient = new HttpClient {
                BaseAddress = new Uri($"https://{endpoint}")
            };
            _channelAuthInterceptor = credentials.ToAsyncAuthInterceptor();

            // TODO: Use options where appropriate.
        }
 private RestGrpcAdapter(RestServiceCollection serviceCollection) =>