Processor

An simply process manager wrapper API for symfony/process to execute and manage sub-processes.

It's an alternative to pcntl-extension, when not installed. This is part of our symplely/coroutine package for handling any blocking i/o process not handle by Coroutine natively.

The library is to provide an easy to use API to control/manage sub processes for windows OS, and other systems, without any additional software extensions installed.

Installation

composer require symplely/processor

Usage

include 'vendor/autoload.php';

use Async\Processor\Processor;

// To set the path to PHP executable for child process
Processor::phpPath('/some/path/version-7.3/bin/php');

$process = \spawn($function, $timeout, $channel)
// Or
$process = Processor::create(function () use ($thing) {
    // Do a thing
    }, $timeout, $channel)
    ->then(function ($output) {
        // Handle success
    })->catch(function (\Throwable $exception) {
        // Handle exception
});

\spawn_run($process);
// Or
$process->run();

// Second option can be used to set to display child output, default is false
\spawn_run($process, true);
// Or
$process->displayOn()->run();

Channel - Transfer messages between a Process

include 'vendor/autoload.php';

use Async\Processor\Channel;
use Async\Processor\ChannelInterface;

$ipc = new Channel();

$process = spawn(function (ChannelInterface $channel) {
    $channel->write('ping'); // same as echo 'ping' or echo fwrite(STDOUT, 'ping')
    usleep(1000);
    echo $channel->read(); // same as echo fgets(STDIN);
    echo $channel->read();
    usleep(1000);
    return 'return whatever';
    }, 300, $ipc)
        ->progress(function ($type, $data) use ($ipc) {
            if ('ping' === $data) {
                $ipc->send('pang' . \PHP_EOL);
            } elseif (!$ipc->isClosed()) {
                $ipc->send('pong' . \PHP_EOL);
                    ->close();
            }
        });

$ipc->setup($process)
\spawn_run($process);

echo \spawn_output($process); // pingpangpongreturn whatever
// Or
echo $ipc->receive(); // return whatever

Event hooks

When creating asynchronous processes, you'll get an instance of LauncherInterface returned. You can add the following event hooks on a process.

$process = spawn($function, $timeout, $channel)
// Or
$process = Processor::create(function () {
        // The second argument is optional, Defaults 300.
        // it sets The maximum amount of time a process may take to finish in seconds
        // The third is optional input pipe to pass to subprocess
    }, int $timeout = 300 , $input = null)
    ->then(function ($output) {
        // On success, `$output` is returned by the process.
    })
    ->catch(function ($exception) {
        // When an exception is thrown from within a process, it's caught and passed here.
    })
    ->timeout(function () {
        // When an time is reached, it's caught and passed here.
    })
    ->progress(function ($type, $data) {
        // A IPC like gateway: `$type, $data` is returned by the process progressing, it's producing output.
        // This can be use as a IPC handler for real time interaction.
    });

There also ->done, part of ->then() extended callback method.

->done(function ($result) {
    // On success, `$result` is returned by the process or callable you passed to the queue.
});
->then(function ($resultOutput) {
        //
    }, function ($catchException) {
        //
    }, function ($progressOutput) {
        //
    }
);

// To turn on to display child output.
->displayOn();

// Stop displaying child output.
->displayOff();

// To display child output, only by third party means once turned on.
->display();

// Processes can be retried.
->restart();
->run();

Error handling

If an Exception or Error is thrown from within a child process, it can be caught per process by specifying a callback in the ->catch() method.

If there's no error handler added, the error will be thrown in the parent process when calling spawn_run() or $process->run().

If the child process would unexpectedly stop without throwing an Throwable, the output written to stderr will be wrapped and thrown as Async\Processor\ProcessorError in the parent process.

Contributing

Contributions are encouraged and welcome; I am always happy to get feedback or pull requests on Github :) Create Github Issues for bugs and new features and comment on the ones you are interested in.

License

The MIT License (MIT). Please see License File for more information.