How does Pool::collect works?

Question

Help me understand how exactly Pool::collect works.

Pool::collect — Collect references to completed tasks

public void Pool::collect          


        

Answer 1

You missed the audit cycle. Task can not be completed immediately, so at first the collect function do not receive positive result. Several times need to check, it requires a cycle.

In the example if infinite is true, always 4 tasks working. Otherwise, if size of queue is equal with pool size (4), it is over, you can exit the loop.

result = md5(rand(1, 2000));
        sleep(rand(1, 5));
        $this->completed = true;
    }

    public function isCompleted()
    {
        return $this->completed;
    }

    public function getResult()
    {
        return $this->result;
    }
}

$infinite = false;
$poolSize = 4;
$queue = array();

$pool = new \Pool($poolSize);
$pool->submit(new Task);
$pool->submit(new Task);
$pool->submit(new Task);
$pool->submit(new Task);


do {
    if($infinite === true){
        $queue = array();
    }

    $pool->collect(function (\Task $task) use (&$queue) {
        if ($task->isCompleted()) {
            echo "Collect task\n";
            $queue[] = $task->getResult();

            return true;
        } else {
            echo "task not complete\n";

            return false;
        }
    });

    $size = sizeof($queue);
    if ($size > 0) {

        echo $size . " result\n";
        print_r($queue);

        if($infinite === true) {
            for ($m = 0; $m < $size; $m++) {
                $pool->submit(new Task);
            }
        } else{
            if($size == $poolSize){
                break;
            }
        }
    }

    usleep(100000);

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