client.js

const { HelloRequest, RepeatHelloRequest, HelloReply } = require("./proto/helloworld_pb.js");
const { GreeterClient } = require("./proto/helloworld_grpc_pb.js");

var client = new GreeterClient("http://" + window.location.hostname + ":8080", null, null);

// simple unary call
var request = new HelloRequest();
request.setName("World");

client.sayHello(request, {}, (err, response) => {
  if (err) {
    console.log(`Unexpected error for sayHello: code = ${err.code}` + `, message = "${err.message}"`);
  } else {
    console.log(response.getMessage());
  }
});

// server streaming call
var streamRequest = new RepeatHelloRequest();
streamRequest.setName("World");
streamRequest.setCount(5);

var stream = client.sayRepeatHello(streamRequest, {});
stream.on("data", (response) => {
  console.log(response.getMessage());
});
stream.on("error", (err) => {
  console.log(`Unexpected stream error: code = ${err.code}` + `, message = "${err.message}"`);
});