I’m using Amphp Parallel. I want to create a task, submit it for execution, and be able to check the execution status without calling await().

For example: a string is passed to a task, the executor falls asleep for 5 seconds, then writes the message “End sleep!” and returns a message that the task is completed.

Here is a working code example using PHP parallel

<?

$executor = function(string $task) {
    
    sleep(5);
    print_r('End sleep!' . PHP_EOL);
    
    return $task . ' is completed!';
};


$task = 'My new task';

$runtime = new parallelRuntime();
$future = $runtime->run($executor, [$task]);

$time = time();

while(true) {
    
    $isComplete = $future->done();
    
    print_r('Time: ' . (time() - $time) . ' - State: ' . ($isComplete ? 'true' : 'false') . PHP_EOL);
    
    if($isComplete) {
        
        print_r('Result: ' . $future->value() . PHP_EOL);
        break;
    }
    
    sleep(1);
}

Result of executing the code:

Time: 0 - State: false
Time: 1 - State: false
Time: 2 - State: false
Time: 3 - State: false
Time: 4 - State: false
End sleep!
Time: 5 - State: true
Result: My new task is completed!

It works as i described above.

Now i want to do the same using Amphp Parallel.

Main script code:

<?
require_once __DIR__ . '/vendor/autoload.php';

use AmpFuture;
use AmpParallelWorker;
use MyTasksMyTask;


$task = 'My new task';

$execution = Workersubmit(new MyTask($task));
$future = $execution->getFuture();

$time = time();

while(true) {
    
    $isComplete = $future->isComplete();
    
    print_r('Time: ' . (time() - $time) . ' - State: ' . ($isComplete ? 'true' : 'false') . PHP_EOL);
    
    if($isComplete) {
        
        print_r('Result: ' . $future->await() . PHP_EOL);
        break;
    }
    
    sleep(1);
}

Code MyTasksMyTask:

<?
namespace MyTasks;
 
use AmpParallelWorkerTask;
use AmpSyncChannel;
use AmpCancellation;


class MyTask implements Task {
    
    public function __construct(private readonly string $task) {}

    public function run(Channel $channel, Cancellation $cancellation): string {
        
        sleep(5);
        print_r('End sleep!' . PHP_EOL);
        
        return $this->task . ' is completed!';
    }
}

The result of running this code:

Time: 0 - State: false
Time: 1 - State: false
Time: 2 - State: false
Time: 3 - State: false
Time: 4 - State: false
End sleep!
Time: 5 - State: false
Time: 6 - State: false
Time: 7 - State: false
Time: 8 - State: false

...

The message “End sleep!” says that the task is completed, but $future->isComplete() continues to return false.

If i rewrite the main script like this:

<?
require_once __DIR__ . '/vendor/autoload.php';

use AmpFuture;
use AmpParallelWorker;
use MyTasksMyTask;


$task = 'My new task';

$execution = Workersubmit(new MyTask($task));
$future = $execution->getFuture();

$time = time();

while(true) {
    
    $result = $future->await();
    
    $isComplete = $future->isComplete();
    
    print_r('Time: ' . (time() - $time) . ' - State: ' . ($isComplete ? 'true' : 'false') . PHP_EOL);
    
    if($isComplete) {
        
        print_r('Result: ' . $result . PHP_EOL);
        break;
    }
    
    sleep(1);
}

I called $future->await() before $future->isComplete() and got this result:

End sleep!
Time: 5 - State: true
Result: My new task is completed!

$future->isComplete() returned true after calling $future->await(), but $future->await() blocked the script from executing.

My ultimate goal is to write a task manager that will distribute tasks to employees and then poll them, get the result and give a new task. Therefore, the blocking that await() does really bothers me.

Can I implement this using Amphp Parallel?

Thanks for any help!