i have a cronjob in php that calculates few business rules (eg: net rev, gross rev, estimated rev, etc... using standard deviation & other math algo)
this cronjob calls multiple cron calls 3 php scripts using exec
for each calls i start a process in background and tell the system that jobs x started. eg:
here's my logic
start
main cron start - message
cron sub 1 start - message
run cron sub 1
cron sub 1 end - message
wait until cron sub 1 stop
process stuff
cron sub 2 start - message
run background cron sub 2 // this will automaticaly send a message when this jobs end
cron sub 3 start - message
run background cron sub 3 // this will automaticaly send a message when this jobs end
main cron end - message
end
what i need to fix is this
if someone runs the job manually and cancel it (ctrl+c) or something bad happen in the cron (fatal error or cannot connect to db) or anything else (like not enough memory)
i want to stop the cronjob and tell what happen and when it stopped so i can start back where it was.
is it possible? thanks
Here's a simple code you have to try/debug:
ReplyDelete<?php
ignore_user_abort(false);
function shutdown() {
echo "shutdown function\n";
}
register_shutdown_function('shutdown');
class shutdown {
function __construct() {
echo "shutdown::construct\n";
}
function __destruct() {
echo "shutdown::destruct\n";
}
}
$s = new shutdown();
declare(ticks = 1);
function sig_handler($signo) {
switch ($signo) {
case SIGTERM:
echo "SIG: handle shutdown tasks\n";
break;
case SIGHUP:
echo "SIG: handle restart tasks\n";
break;
case SIGUSR1:
echo "SIG: Caught SIGUSR1\n";
break;
case SIGINT:
echo "SIG: Caught CTRL+C\n";
break;
default:
echo "SIG: handle all other signals\n";
break;
}
return;
}
echo "Installing signal handler...\n";
pcntl_signal(SIGTERM, "sig_handler");
pcntl_signal(SIGHUP, "sig_handler");
pcntl_signal(SIGUSR1, "sig_handler");
pcntl_signal(SIGINT, "sig_handler");
echo "Generating signal SIGTERM to self...\n";
# killing the script using bad memory allocation
/*
ini_set('memory_limit', '1K');
$data = '';
for($i = 0; $i < 1000; $i++) {
$data .= str_repeat($i . time(), time());
}
*/
# simulating CTRL+C
// for($i = 0; $i < 100000000; $i++) { } // don't forget to press CTRL+C
echo "Done\n";
if the cronjob runs normally you will get:
shutdown::construct
Installing signal handler...
Generating signal SIGTERM to self...
Done
shutdown function
shutdown::destruct
if you get a Fatal error:
shutdown::construct
Installing signal handler...
Generating signal SIGTERM to self...
PHP Fatal error: Possible integer overflow in memory allocation (11 * 1321404273 + 1) in /var/www/domain.com/php.php on line 51
shutdown function
if you kill the process:
kill <processid>
shutdown::construct
Installing signal handler...
Generating signal SIGTERM to self...
SIG: handle shutdown tasks
Done
shutdown function
shutdown::destruct
you can use posix_kill(posix_getpid(), <signal you like>); in each cases also.
read more:
http://php.net/manual/en/function.pcntl-signal.php
http://en.wikipedia.org/wiki/Signal_%28computing%29
http://users.actcom.co.il/~choo/lupg/tutorials/signals/signals-programming.html
If this is a bash script, you can trap the ctrl+c signal like so:
ReplyDeleteis_borked()
{
echo "Somebody set up us the bomb"
exit
}
trap is_borked SIGINT
It'd be up to you to keep track (via variable?) at which step this happened, if you need some kind of a cleanup.