日期临近时通知用户

function setReminder(date) {
    const now = new Date();
    const timeDiff = date - now;

    if (timeDiff > 0) {
        setTimeout(() => {
            alert('提醒：时间即将到来！');
            // 这里可以调用发送通知的API
        }, timeDiff);
    } else {
        alert('时间已经过去！');
    }
}

const reminderDate = new Date('2023-10-31T12:00:00');
setReminder(reminderDate.getTime());

const express = require('express');
const app = express();
const cron = require('node-cron');

app.get('/set-reminder', (req, res) => {
    const reminderDate = new Date(req.query.date);
    const job = cron.schedule(`0 ${reminderDate.getMinutes()} ${reminderDate.getHours()} ${reminderDate.getDate()} ${reminderDate.getMonth() + 1} ${reminderDate.getFullYear()}`, () => {
        // 这里可以调用发送通知的API
        console.log('提醒：时间即将到来！');
    });

    res.send('提醒设置成功！');
});

app.listen(3000, () => {
    console.log('服务器运行在 http://localhost:3000');
});