How to write asynchronous web service run in background php

im up to write background processing web service using php that need to run in background even user closed the browser is there any way to do this using php ?

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Yes im working on large web project (pay roll) using symfony/php. it needs to process in every mo开发者_C百科nth when payroll user comes and click the process button. then payroll should process without apache server time out. for do that i hope to wirte asynchronous web service that run in background.

As commentor said, you should use a CRON job as it's best suited for this kind of problems. However, you need to launch your job on the click of a user. Here is what I'd use:

1. On the click of a user, create a row in some table, or create a file with needed parameter to execute the task. Basically it says to the CRON 'hey, you need to launch the task'.
2. Setup a CRON job to look after that row/file every minute, and launch the task if the row/file is found. Delete the file before launching the task, or parallels tasks could happen.
3. If you need to tell your user when the payroll is done, make the task create another row/file to show that the CRON ended, and with javascript refresh your user page every 30s/1min, and stop the automatic refresh when the new row/file is found, and display the appropriate output/notice message.

Take a look at this article. Depending on what you're doing this can be much better than a CRON job, most specifically, if you want to take action immediately. CRON jobs are limited to running at most, once per minute, with this approach, you can begin handling the request in the background immediately.

// this script can run forever
set_time_limit(0);
 
// tell the client the request has finished processing
header('Location: index.php');  // redirect (optional)
header('Status: 200');          // status code
header('Connection: close');    // disconnect
 
// clear ob stack 
@ob_end_clean();
 
// continue processing once client disconnects
ignore_user_abort();
 
ob_start();
/* ------------------------------------------*/
/* this is where regular request code goes.. */
 
/* end where regular request code runs..     */
/* ------------------------------------------*/
$iSize = ob_get_length();
header("Content-Length: $iSize");
 
// if the session needs to be closed, persist it
// before closing the connection to avoid race
// conditions in the case of a redirect above
session_write_close();
 
// send the response payload to the client
@ob_end_flush();
flush();
 
/* -------------------------------------------*/
/* code here runs after the client disconnect */