API キーで API アクセスを制限する

def run(
    host, port, api_key, auth_token, timeout, use_tls, servername_override, ca_path

private static final class Interceptor implements ClientInterceptor {
  private final String apiKey;
  private final String authToken;

  private static Logger LOGGER = Logger.getLogger("InfoLogging");

  private static Metadata.Key<String> API_KEY_HEADER =
      Metadata.Key.of("x-api-key", Metadata.ASCII_STRING_MARSHALLER);
  private static Metadata.Key<String> AUTHORIZATION_HEADER =
      Metadata.Key.of("authorization", Metadata.ASCII_STRING_MARSHALLER);

  public Interceptor(String apiKey, String authToken) {
    this.apiKey = apiKey;
    this.authToken = authToken;
  }

  @Override
  public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
      MethodDescriptor<ReqT,RespT> method, CallOptions callOptions, Channel next) {
    LOGGER.info("Intercepted " + method.getFullMethodName());
    ClientCall<ReqT, RespT> call = next.newCall(method, callOptions);

    call = new ForwardingClientCall.SimpleForwardingClientCall<ReqT, RespT>(call) {
      @Override
      public void start(Listener<RespT> responseListener, Metadata headers) {
        if (apiKey != null && !apiKey.isEmpty()) {
          LOGGER.info("Attaching API Key: " + apiKey);
          headers.put(API_KEY_HEADER, apiKey);
        }
        if (authToken != null && !authToken.isEmpty()) {
          System.out.println("Attaching auth token");
          headers.put(AUTHORIZATION_HEADER, "Bearer " + authToken);
        }
        super.start(responseListener, headers);
      }
    };
    return call;
  }
}

func main() {
	flag.Parse()

	// Set up a connection to the server.
	conn, err := grpc.Dial(*addr, grpc.WithInsecure())
	if err != nil {
		log.Fatalf("did not connect: %v", err)
	}
	defer conn.Close()
	c := pb.NewGreeterClient(conn)

	if *keyfile != "" {
		log.Printf("Authenticating using Google service account key in %s", *keyfile)
		keyBytes, err := ioutil.ReadFile(*keyfile)
		if err != nil {
			log.Fatalf("Unable to read service account key file %s: %v", *keyfile, err)
		}

		tokenSource, err := google.JWTAccessTokenSourceFromJSON(keyBytes, *audience)
		if err != nil {
			log.Fatalf("Error building JWT access token source: %v", err)
		}
		jwt, err := tokenSource.Token()
		if err != nil {
			log.Fatalf("Unable to generate JWT token: %v", err)
		}
		*token = jwt.AccessToken
		// NOTE: the generated JWT token has a 1h TTL.
		// Make sure to refresh the token before it expires by calling TokenSource.Token() for each outgoing requests.
		// Calls to this particular implementation of TokenSource.Token() are cheap.
	}

	ctx := context.Background()
	if *key != "" {
		log.Printf("Using API key: %s", *key)
		ctx = metadata.AppendToOutgoingContext(ctx, "x-api-key", *key)
	}
	if *token != "" {
		log.Printf("Using authentication token: %s", *token)
		ctx = metadata.AppendToOutgoingContext(ctx, "Authorization", fmt.Sprintf("Bearer %s", *token))
	}

	// Contact the server and print out its response.
	name := defaultName
	if len(flag.Args()) > 0 {
		name = flag.Arg(0)
	}
	r, err := c.SayHello(ctx, &pb.HelloRequest{Name: name})
	if err != nil {
		log.Fatalf("could not greet: %v", err)
	}
	log.Printf("Greeting: %s", r.Message)
}

const makeGrpcRequest = (JWT_AUTH_TOKEN, API_KEY, HOST, GREETEE) => {
  // Uncomment these lines to set their values
  // const JWT_AUTH_TOKEN = 'YOUR_JWT_AUTH_TOKEN';
  // const API_KEY = 'YOUR_API_KEY';
  // const HOST = 'localhost:50051'; // The IP address of your endpoints host
  // const GREETEE = 'world';

  // Import required libraries
  const grpc = require('grpc');
  const path = require('path');

  // Load protobuf spec for an example API
  const PROTO_PATH = path.join(__dirname, '/protos/helloworld.proto');
  const protoObj = grpc.load(PROTO_PATH).helloworld;

  // Create a client for the protobuf spec
  const client = new protoObj.Greeter(HOST, grpc.credentials.createInsecure());

  // Build gRPC request
  const metadata = new grpc.Metadata();
  if (API_KEY) {
    metadata.add('x-api-key', API_KEY);
  } else if (JWT_AUTH_TOKEN) {
    metadata.add('authorization', `Bearer ${JWT_AUTH_TOKEN}`);
  }

  // Execute gRPC request
  client.sayHello({name: GREETEE}, metadata, (err, response) => {
    if (err) {
      console.error(err);
    }

    if (response) {
      console.log(response.message);
    }
  });
};