Table of Contents

• Installation
• Configuration
• Usage
• Run command
• Command events

DaemonBundle

Allows you to create daemonized commands with the React event-loop component.

Installation

Via composer :

composer require m6web/daemon-bundle

Note:

• If you are using a symfony version >= 4.3 use the lastest version
• For symfony versions between 2.3 and 3.0, you can use m6web/daemon-bundle:^1.4
• For PHP versions >=5.5.9 and <7.0 support, you can use m6web/daemon-bundle:^3.0

For more information about installation of plugin refers the documentation of symfony for your version.

Configuration

You can optionally define events which are triggered each X iterations:

m6_web_daemon:
    iterations_events:
        -
            count: 10
            name: Path\From\Your\Project\Event\EachTenEvent
        -
            count: 5
            name: Path\From\Your\Project\Event\EachFiveEvent

Your event need to extends the AbstractDaemonEvent like following:

<?php

namespace Path\From\Your\Project\Event;

use M6Web\Bundle\DaemonBundle\Event\AbstractDaemonEvent;

class EachFiveEvent extends AbstractDaemonEvent
{
}

This bundle use the PSR-14 implementation for event dispatcher so you need to register the symfony event dispatcher in your config/services.yaml like this:

# config/services.yaml
services:
    # ... others declarations

    Psr\EventDispatcher\EventDispatcherInterface: "@event_dispatcher"

Usage

This command uses the event-loop component which ReactPHP is used to run loops and other asynchronous tasks.

<?php

namespace App\Command;

use M6Web\Bundle\DaemonBundle\Command\DaemonCommand;
use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;

class DaemonizedCommand extends DaemonCommand
{
    protected function configure()
    {
        $this
            ->setName('daemonized:command')
            ->setDescription('My daemonized command');
    }

    protected function setup(InputInterface $input, OutputInterface $output): void
    {
        // Set up your daemon here

        // Add your own optional callback : called every 10 iterations
        $this->addIterationsIntervalCallback(10, [$this, 'executeEveryTenLoops']);

        // You can add your own Periodic Timer,
        // Here this timer will be called every 0.5s
        $daemon = $this;
        $this->loop->addPeriodicTimer(0.5, function ($timer) use ($daemon) {
            // It's the last loop, cancel the timer.
            if ($daemon->isLastLoop()) {
                $daemon->loop->cancelTimer($timer);
            }
        });
    }

    /**
     * Execute is called at every loop
     */
    protected function execute(InputInterface $input, OutputInterface $output)
    {
        $output->writeln("Iteration");

        // This method helps to give back the CPU to the react-loop.
        // So you can wait between two iterations if your workers has nothing to do.

        $this->setNextIterationSleepingTime(1000000); // Every second
    }

    /**
     * executeEveryTenLoops is called every 10 loops
     */
    protected function executeEveryTenLoops(InputInterface $input, OutputInterface $output): void
    {
        $output->writeln("Iteration " . $this->getLoopCount());
    }
}

You also need to declare your command under the services:

# config/services
services:
    # ... others declarations

    App\Command\DaemonizedCommand:
        parent: M6Web\Bundle\DaemonBundle\Command\DaemonCommand
        tags:
            - console.command

For information, you need to declare the autowire and autoconfigure parameters (to false) only if you have defaults parameters for services (under _default)

Run command

You can run a daemonized command as any other Symfony command with bin/console. DaemonCommand parent class provide additional options :

• --run-once - Run the command just once
• --run-max - Run the command x time
• --memory-max - Gracefully stop running command when given memory volume, in bytes, is reached
• --shutdown-on-exception - Ask for shutdown if an exception is thrown
• --show-exceptions - Display exceptions on command output stream

Command events

Daemonized command trigger the following events :

• DaemonEvents::DAEMON_START
• DaemonEvents::DAEMON_LOOP_BEGIN
• DaemonEvents::DAEMON_LOOP_EXCEPTION_STOP
• DaemonEvents::DAEMON_LOOP_EXCEPTION_GENERAL
• DaemonEvents::DAEMON_LOOP_MAX_MEMORY_REACHED
• DaemonEvents::DAEMON_LOOP_ITERATION
• DaemonEvents::DAEMON_LOOP_END
• DaemonEvents::DAEMON_STOP