Laravel Commands, Pthreads and Closure

Question

There is a need to perform a specific process multiple threads. I learned about the extension for php - pthreads.

For example, a simple script outside Laravel works fine and I liked the results. I decided to move in Laravel, and faced with the problem. Of course I searched in google, found some questions on stackoverflow, where replied the author of extension. But me did not help his answers, so I ask you to help me.

Answered Question extension author.

There is a class App\Commands\QuestionsParserCommand. Inside I created an instance of the class App\My\Questions\QuestionsParser and call the method init(). Then the code of the method init():

// Create a pool
$pool = new Pool($this->threads, ParserWorkers::class);

// Create a thread class
$thread = new class extends Threaded
{
    public function run()
    {
      // The class will receive data from a provider
      // that will be shared between threads through ParserWorkers.
      // It will work with the API and store the data in the database.
      // The need to work with the threads,
      // because the data for processing an incredible amount.

      echo '+';
    }
};

// Start a threads
for ($i = 0; $i < $this->threads; $i++) {
    $pool->submit($thread);
}

$pool->shutdown();

Class ParserWorkers inherits from Worker and yet has an empty method run().

As a result, I run the script and get a message in the log of php:

[13-Oct-2016 11:27:35 Europe/Moscow] PHP Fatal error:  Uncaught Exception: Serialization of 'Closure' is not allowed in [no active file]:0
Stack trace:
#0 {main}
    thrown in [no active file] on line 0

Information: Laravel 5.2.43, php 7.0.8, Windows

Thank you all!

Answer 1

First you can get acquainted with the strategy of the author of the library: https://github.com/krakjoe/pthreads-autoloading-composer

The strategy used here ensures that each thread (Worker) gets a thread local copy of the framework, or whatever is being loaded, but does not break the abilities of objects that descend from pthreads.

---

Secondly, to start working with laravel features (like Service Providers, Facades, Helpers, etc), you need to initialize laravel.

I looked at how to initialize the application in the tests/CreatesApplication.php file. The code below shows how to do this for Laravel 5.7 with php 7.2.

Important: specify the correct path to autoload.php and app.php relative to the Autoloader.php file location.

namespace App\Console\Commands;

use Worker;

use Illuminate\Contracts\Console\Kernel;

class Autoloader extends Worker
{
    public function run()
    {
        require __DIR__. '/../../../vendor/autoload.php';
        $app = require __DIR__.'/../../../bootstrap/app.php';
        $app->make(Kernel::class)->bootstrap();
    }

    public function start($options = PTHREADS_INHERIT_ALL)
    {
        return parent::start(PTHREADS_INHERIT_INI);
    }

}

namespace App\Console\Commands;

use Exception;
use Threaded;

class OperatorThread extends Threaded
{
    /**
     * @var OperatorThreaded
     */
    private $operator;
    private $error;

    public function __construct(OperatorThreaded $operator)
    {
        $this->operator = $operator;
    }

    public function run()
    {
        try {
            $this->operator->handle();
        } catch (Exception $exception) {
            $this->error = (string) $exception;
        }
    }

    public function getError() {
        return $this->error;
    }

}

namespace App\Console\Commands;

class OperatorThreaded
{
    private $i;

    public function __construct($i)
    {
        $this->i = $i;
    }

    public function handle()
    {
        sleep(rand(1,3));
        if (app()->isBooted()) {
            echo $this->i . PHP_EOL;
        }
    }

}

---

Now you can use Laravel with pthreads:

namespace App\Console\Commands;

use Pool;

use Illuminate\Console\Command;

class Test extends Command
{
    protected $description = 'test';
    protected $signature = 'test';

    public function handle()
    {
        $operators = [];
        for ($i=0; $i<5; $i++) {
            $operators[] = new OperatorThreaded($i);
        }

        $pool = new Pool(count($operators), Autoloader::class);
        foreach ($operators as $operator) {
            $thread = new OperatorThread($operator);
            $pool->submit($thread);
        }

        while ($pool->collect());
        $pool->shutdown();
    }
}

$ php artisan test
1
2
4
0
3

Answer 2

foreach ($this->pool as $w) {
   $w->start(PTHREADS_INHERIT_ALL ^ PTHREADS_INHERIT_CLASSES);
}