simpleSpan.js

const tracer = ... // See example above

tracer.scoped(() => {
  const id = tracer.createRootId();
  
  tracer.setId(id);
  tracer.recordAnnotation(new zipkin.Annotation.ClientSend());
  tracer.recordAnnotation(new zipkin.Annotation.Rpc("My Span"));

  fetch("http://google.de").then(res => res.json()).then(result => {
    tracer.scoped(() => {
      tracer.setId(id);
      tracer.recordBinary("result", JSON.stringify(result));
      tracer.recordAnnotation(new zipkin.Annotation.ClientRecv());    
    });
  });

});