php，如何在后台为消费者创建/保持服务？
im running an ec2 instance, with ubuntu 12.04.
i am using aws infastructure, and right now im trying to implement a consumer worker which will consume an sqs queue (queue of msgs, not very important).
to do that i created a php file, which "harvest" the queue for 30 seconds. on top i have a crontab running this page every 30 seconds.
what is a more elegant/proper solution? how do i make a background php proccess, and how i do check if its alive, and kill it restart it, if needed?
- just a clarification - i am asking about the process which consumes the queue, regardless of which/what mechanizem is selected (sqs, rabbitMQ)
thanks for your help
create a monitor script utilizing the class process (which i copied from php docs), which launches your worker script if the process is not running. the monitor script can keep the pid in a file.
then simply add the monitor to crontab.
class Process{
private $pid;
private $command;
public function __construct($cl=false){
if ($cl != false){
$this->command = $cl;
$this->runCom();
}
}
private function runCom(){
$command = 'nohup '.$this->command.' > /dev/null 2>&1 & echo $!';
exec($command ,$op);
$this->pid = (int)$op[0];
}
public function setPid($pid){
$this->pid = $pid;
}
public function getPid(){
return $this->pid;
}
public function status(){
$command = 'ps -p '.$this->pid;
exec($command,$op);
if (!isset($op[1]))return false;
else return true;
}
public function start(){
if ($this->command != '')$this->runCom();
else return true;
}
public function stop(){
$command = 'kill '.$this->pid;
exec($command);
if ($this->status() == false)return true;
else return false;
}
}
