使用PHP设置一个cron作业并永远重新访问

Question

I have a file on the server that extract some data from pages, like a crawler. Ok, now, sometimes, the execution of the script takes 5 seconds, but sometimes takes even 1 minute or 2.

Setting a cron job for accessing the file at 2, 3, or 5 minute is not comfortable for me, because I need this crawler to run as fast as possible.

So my question is:

Can I set a cron job to run, let's say, every 5 minutes and set php to re-run the script again and again and again ?

More clear:

*/5 * * * * wget -O - site.com/index.php?cron >/dev/null 2>&1

index.php?cron

function cron_action()
{
    //some action here

    // Call again the function
    cron_action();
}

cron_action();

As I don't understand very well how does cron job react at my script, I don't know either what will happen when, on another 5 minutes, the cron job will acces the url again.

I will be in a infinity loop ?

How you would do that ? I need some advices please. I really need to set the cron job run faster and, in my opinion, the functions from php must be recalled forever.

Answer 1

Setup cronjob:

* * * * * php /path/to/your/file.php --arg1=value1 --arg2=value2 >> /dev/null 2>&1

Your file.php

<?php

//test your args
var_dump($argv);

$minute = date('i',time());

//run every 10 minutes
if(intval($minute)%10==0){
    //run your cron job code here
    cron_action();
}
else{
    //do other code
}

function cron_action()
{
    //do stub
}

And this is how to use cronjob with laravel https://laravel.com/docs/5.3/scheduling, you will learn from that.