如何使用 Node-Schedule 运行 Cron Task Once

Question

我使用 node-schedule 来安排一个任务在特定时间只执行一次。文档显示对我来说：

Date-based Scheduling: Say you very specifically want a function to execute at 5:30am on December 21, 2012. Remember - in JavaScript - 0 - January, 11 - December.
const schedule = require('node-schedule');
const date = new Date(2012, 11, 21, 5, 30, 0);

const job = schedule.scheduleJob(date, function(){
  console.log('The world is going to end today.');
});

但是这段代码运行每分钟都会执行一次任务，我只希望它运行在此处指定的特定时间只执行一次任务：

const date = new Date(2012, 11, 21, 5, 30, 0);

这里的日期是默认的。我在我的代码中将其更改为未来日期，如下所示：

const now = new Date().getTime();
const seconds = 180;
const parsedDate = new Date(Date.parse(now));
const date = new Date(parsedDate.getTime() + (1000 * seconds));
schedule.scheduleJob(date, function(data) {
    console.log("Job ran @", new Date().toString());
});

在这里，我只想在从当前日期算起 180 秒（3 分钟）后执行一项作业。但控制台结果显示控制台日志在部署后每分钟写入一次：

>  Job ran @ Tue Mar 16 2021 08:56:00 GMT+0000 (GMT)
>  Job ran @ Tue Mar 16 2021 08:57:00 GMT+0000 (GMT)
>  Job ran @ Tue Mar 16 2021 08:58:00 GMT+0000 (GMT)
>  Job ran @ Tue Mar 16 2021 08:59:00 GMT+0000 (GMT)

感谢您的帮助。

Answer 1

我通过在我的代码中添加时区来解决这个问题。我使用另一个 post 的 answer。这里的功能是在日期功能中添加时区功能，方便快捷。

This should solve your problem, please feel free to offer fixes. This method will account also for daylight saving time for the given date.

  Date dateWithTimeZone = (timeZone, year, month, day, hour, minute, second) => {
  let date = new Date(Date.UTC(year, month, day, hour, minute, second));

  let utcDate = new Date(date.toLocaleString('en-US', { timeZone: "UTC" }));
  let tzDate = new Date(date.toLocaleString('en-US', { timeZone: timeZone }));
  let offset = utcDate.getTime() - tzDate.getTime();

  date.setTime( date.getTime() + offset );

  return date;
};

然后我的代码看起来像这样：

schedule.scheduleJob(dateWithTimeZone("Europe/Istanbul",
      req.body.year, req.body.month, req.body.day, req.body.hour,
      req.body.minute, req.body.second), function(data) {
    console.log("Job ran @", new Date().toString());
});

最后它对我来说很好用。我可以安排在我喜欢的时区内只执行一次作业。

感谢您的关注。关于...

Answer 2

我找到了一种安排 cron 作业的简单方法。

const schedule = require('node-schedule');
const moment = require('moment');

const rule = scheduled.RecurrenceRule();

let time = '2021-07-30 14:20:00';
rule.tz = 'Asia/Kolkata';
rule.year = moment(time).year();
rule.month = moment(time).month();
rule.date = moment(time).date();
rule.hour = moment(time).hours();
rule.minute = moment(time).minutes();
rule.second = moment(time).seconds();
schedule.scheduleJob(rule, async function () {
     console.log("Scheduled")
});

如何使用 Node-Schedule 运行 Cron Task Once

How to Run Cron Task Once with Node-Schedule

cron

date

node.js

server

node-schedule