title: How to use async/await pattern with gRPC Web?
body: <p>I'm developing a Vue.js web application and I'm using gRPC to assure the communication.</p>
  <p>In the frontend, I'm using the web version of gRPC: <code>grpc-web</code>.</p>
  <p>Everything is working just fine; however, when I'm doing an API call in my store, e.g.:</p>
  <pre><code>async fetchEcho() {
      const echoService = new EchoServiceClient('http://localhost:8080', null, null);
  
      const request = new EchoRequest();
      request.setMessage('Hello World!');
  
      const call = echoService.echo(request, {'custom-header-1': 'value1'},
        (err: grpcWeb.Error, response: EchoResponse) =&gt; {
          console.log(response.getMessage());
      });
  }
  </code></pre>
  <p>How can I use the <code>async/await</code> pattern when making the call in my Vue file, e.g.:</p>
  <pre><code>await fetchEcho();
  // ...
  </code></pre>
  <p>And await until the API call has finished to resume my the course of my program?</p>
  <p>Thanks!</p>