seankndy / daemon
PHP package for creating and managing daemons
Requires
- php: ^8.1
- clue/socket-raw: >=1.3
- psr/log: ^3.0
- symfony/event-dispatcher: ^4.1
This package is not auto-updated.
Last update: 2025-03-25 21:45:31 UTC
README
$ composer require seankndy/daemon
Usage overview
On each iteration of the main loop, producers are called which should provide a task to fork/run.
Producers can be callables or objects that implement SeanKndy\Daemon\Tasks\Producer
. Producers should return null
if there is no task to perform otherwise a SeanKndy\Daemon\Tasks\Task
or callable
. SeanKndy\Daemon\Tasks\Task
has 3 methods:
init()
- Called from parent process just before child is forked.
run()
- Called from within forked process (child work)
finish(int $status)
- Called from parent when process exits
So if you need to perform any initialization or teardown of as children are spawned/exiting, then
you'll want to make your own task classes implementing SeanKndy\Daemon\Tasks\Task
rather than using
a simple closure.
There are various events you can listen for (use SeanKndy\Daemon\Daemon::addListener()
):
SeanKndy\Daemon\DaemonEvent::START
- When daemon starts
SeanKndy\Daemon\DaemonEvent::STOP
- When daemon stops
SeanKndy\Daemon\DaemonEvent::DAEMONIZED
- When daemonized (backgrounded)
SeanKndy\Daemon\DaemonEvent::LOOP_ITERATION
- Called at the end of each loop iteration
SeanKndy\Daemon\Processes\Event::START
- New process started
SeanKndy\Daemon\Processes\Event::EXIT
- New process exited
SeanKndy\Daemon\Processes\Event::ITERATION
- Every main loop iteration this is fired for each running process
<?php use SeanKndy\Daemon\Daemon; use SeanKndy\Daemon\Processes\Event as ProcessEvent; $maxProcesses = 50; $quietTime = 1000000; $childTimeout = 30; $daemon = new Daemon($maxProcesses, $quietTime, $childTimeout); // $producer can be a callable or an object that implements SeanKndy\Daemon\Tasks\Producer // it should produce work to do (which is also a callable or an object implementing SeanKndy\Daemon\Tasks\Task) // // if multiple producers are added, they will be round-robined $number = 0; $producer = function() use (&$number) { if ($number >= 10) return null; $number++; // this is the "task" or the code to run within the forked child return function() use ($number) { echo "hello from child $number, my pid is " . getmypid() . "\n"; return 0; // child exit value }; }; $daemon->addProducer($producer); // optional, signal catching $daemon->addSignal(SIGTERM, function ($signo) { // SIGTERM caught, handle it here }); // optional, example event listeners $daemon->addListener(ProcessEvent::START, function ($event) { // process $event->getProcess() started }); $daemon->addListener(ProcessEvent::EXIT, function ($event) { // process $event->getProcess() exited }); $daemon->setDaemonize(false); // don't fork to background $daemon->start();
Inter-process Communication example
You can use \SeanKndy\Daemon\IPC\Socket
to send message from child to parent using socket pairs.
Here is an example of doing that:
<?php use SeanKndy\Daemon\Tasks\Task; class MyTask implements Task { private $ipc; /** * Initialize task (main thread) * * @return void */ public function init() : void { $this->ipc = new \SeanKndy\Daemon\IPC\Socket(); } /** * Do the work (child thread) * * @return int */ public function run() : int { // do something useful in child and generate $interestingData $this->ipc->send($interestingData); $this->ipc->close(); } /** * Cleanup (main thread) * * @var int $status Exit status of child thread * @return void */ public function finish(int $status) : void { if ($this->ipc->hasMessage()) { $interestingData = $this->ipc->receive(); // $interestingData now in parent process } $this->ipc->close(); } }