$("#go_login").click(function () {

  var url = "http://127.0.0.1:8000/login";

  var xhr = new XMLHttpRequest();
  xhr.open("POST", url);

  xhr.setRequestHeader("accept", "application/json");
  xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");

  xhr.onreadystatechange = function () {
    if (xhr.readyState === 4) {
      console.log(xhr.status);
      console.log(xhr.responseText);
      alert('登入成功')
      window.location.replace( "/index" )
    }
  };
  var data = "grant_type=&username="+$('#username').val()+"&password=qwe&scope=&client_id=&client_secret=";
  xhr.send(data);

});