javascript - 使用 Firebase 的服务器端计算

Question

给定开始时间/日期和持续时间，我如何进行服务器端计算以确定对象是“finished”、“in progress”，还是“即将到来”

--Show
  --duration: "144"
  --startDate: "2015-11-10"
  --startTime: "14:00"
  --status: "?"

用于确定节目是否已经开始的客户端 javascript:

// if negative, then show hasn't started yet
var time = (-(startdate.getTime() - currentdate.getTime()) / 1000 / 60); 

客户端 javascript 判断节目是否已经运行完毕:

// if negative, then show has finished
var timeLeft = channelDuration - timerStartTime;

Answer 1

无法在 Firebase 上运行您自己的服务器端代码。见:

• Common Firebase application architectures
• Firebase Hosting with own server node.js
• How would I run server-side code in Firebase?
• How to write custom code (logic) when using firebase

但是您可以存储服务器端时间戳，这似乎是您想要做的:

ref.child('Show/startTimestamp').set(Firebase.ServerValue.TIMESTAMP);

然后您可以获得尚未开始的节目:

var shows = ref.child('Shows');
ref.orderByChild('startTimeStamp').startAt(Date.now()).on(...