Parallel function on website

Question

I have a class that generates a file .xls for download. The problem is that it has more than 30,000 entries, so it takes about 10 minutes to generate. And in that time I have to keep the page open loading.
I remember some sites that I used to convert files in which after finishing the upload I could close the page, the browser and even turn off the computer that when the process was finished I would receive an email with my file attached.
My intention is to do the same with this file. The user clicks to download, then is redirected to a page that says he will receive the file in the email and meanwhile he can close the page and do something else.

In my researches I ended up finding the pcntl_fork(), that seemed to be perfect, until I discovered that it only works if I rotate the .php directly from the terminal. I couldn’t find anything that works on websites.

Answer 1

I solved it in a very simple way. I modified the generate button .xlsx so that instead of generating, it calls in the terminal the code it generates with shell_exec("php nomeDoArquivo.php"), but even so he is waiting for the output of the terminal, then ended up taking equal.

To resolve this, as the terminal output does not interest me¹ I asked to ignore it by modifying the command to:

$your_command = "php nomeDoArquivo.php";
shell_exec( $your_command . "> /dev/null 2>/dev/null &" );

Source: Mat

[1]: Great care when ignoring the output, if you have any error in the process you will never know. As my script already sends an attached email I already set it to when it is error send an email to me with the error message.

Answer 2

A solution, perhaps not very elegant, would be to queue this file (managed in a database table and/or directory), and on the server would have a cronjob PHP script that would do the job of generating the file and sending it to the email from time to time.