js: use web notification as a promise.

js: notification-as-promise.js

function notifyMessage(message, options, callback) {
  if (Notification && Notification.permission === 'granted') {
    var notification = new Notification(message, options);
    callback(null, notification);
  } else if (Notification.requestPermission) {
    Notification.requestPermission(function (status) {
      if (Notification.permission !== status) {
        Notification.permission = status;
      }
      if (status === 'granted') {
        var notification = new Notification(message, options);
        callback(null, notification);
      } else {
        callback(new Error('user denied'));
      }
    });
  } else {
    callback(new Error('doesn\'t support Notification API'));
  }
}
function notifyMessageAsPromise(message, options) {
  return new Promise(function (resolve, reject) {
    notifyMessage(message, options, function (error, notification) {
      if (error) {
        reject(error);
      } else {
        resolve(notification);
      }
    });
  });
}
// 运行示例
notifyMessageAsPromise("Hi!").then(function (notification) {
    console.log(notification);// 通知对象
}).catch(function(error){
    console.error(error);
});