Promise と XMLHttpRequestオブジェクトでweb APIのデータを読み込む

const url = "http://api.open-notify.org/astros.json";

function getJson(url) {
  return new Promise((resolve, reject) => {
    const req = new XMLHttpRequest();
  
    req.addEventListener("load", () => resolve(JSON.parse(req.response)  ));
  
    req.addEventListener("error", (error) => {
      reject(error);
    });
  
    req.open("GET", url);
    req.send();
  });
}

getJson(url)
.then((spaceDate) => console.log(spaceDate.people))
.catch((value) => console.log(new Error("Can not load!!")));