我怎样才能创建在几天后过期的URL？

I am working on a project which need to send a video link to any email. But this video link will expire after 3 days automatically and video url should not work. How can I do it? Any help will be appreciated.

You have to store the videos Ids along with their creation dateTime in a database, so you can query them in your application layer (PHP).

the structure of your URL you are going to serve could be something like this

 domain/videos.php?video_id=123456

the database table

 -- videos table
 +----------+---------------------------+
 | video_id |    creation_datetime      |
 +----------+---------------------------+
 |  123456  |    2017-07-18 14:21:19    |
 |  123457  |    2017-07-16 11:21:50    | 
 +----------+---------------------------+

The php script videos.php

<?php 
if(empty($_GET['video_id'])){
    die('no video to show');//TODO: proper msg
}
$mysqli = new mysqli("example.com", "user", "password", "database");

$query = "SELECT video_id FROM videos WHERE video_id = ? AND creation_datetime >= ?";
$stmt = $mysqli->prepare($query);
!$stmt ? die('error') : "";
//before 3 days
$stmt->bind_param('ss', $_GET['video_id'], date("Y-m-d H:i:s", time() - 3 * 24 * 60* 60));
$stmt->execute();
$result = $stmt->get_result();
if($result->num_rows){
    //give the video
}else{
    die('sorry, the video is expired');
}
exit;

Now, depending on the time I write this domain/videos.php?video_id=123456 would be served and domain/videos.php?video_id=123457 is expired