PHP：从初始日期起每24小时发布一次Cron作业

Question

I was wondering if I could get some help.

I have a cronjob that is run every 5 mins.

I also have a number of entries in my DB with a 'start date' formatted like

 'yyyy-mm-dd HH:mm:ss'

What I want to do is run a specific command for each entry 24 hrs after the start date.

So for instance, if an entry has a start date of 2016-11-18 12:08:44 , I want to run a command on that entry at 2016-11-19 12:08:44 ... Because the cron only runs every 5 mins, I don't expect to be exactly spot on 24hrs, but as close (5 mins each way) as possible.

Is there any chance someone could give me an example of how I could achieve this in PHP?

Much appreciated.

Answer 1

You should do the job like this :

1. Add a column "desired launch date" in the DB (Nullable).
2. Write a php script what calculate all 'desired launch date' from 'start_date' (and update the DB with calculed date).
3. Add block on this PHP script that initialize current datetime and compare with 'desired launch date' with an interval of 10 minutes.

EDIT :

Here a piece of source code, not tested !

$datetime = new \Datetime();
$timestamp = $datetime->getTimestamp();

$datetime_desired_launch = new \Datetime($your_formatted_datetime_from_db);
$desired_timestamp = $datetime_desired_launch->getTimestamp();

// I have manipulate timestamp for more efficiency
$launch_min_interval = $desired_timestamp - 5 * 3600; // - 5 minutes
$launch_max_interval = $desired_timestamp + 5 * 3600; // + 5 minutes

if ($timestamp >= $launch_min_interval && $timestamp <= $launch_max_interval) {
  // Here launch action...
}

Be careful of timezones !

Hope this help !

Answer 2

You can use crontab to lance a script each 5 min

In this script you can check for date and lance the others scripts