PHP下用Swoole實現Actor併發模型的方法

這篇文章主要介紹了PHP下用Swoole實現Actor併發模型的方法，文中通過示例代碼介紹的非常詳細，對大家的學習或者工作具有一定的參考學習價值，需要的朋友們下面隨着小編來一起學習學習吧

什麼是Actor？

Actor對於PHPer來說，可能會比較陌生，寫過Java的同學會比較熟悉，Java一直都有線程的概念（雖然PHP有Pthread,但不普及）,它是一種非共享內存的併發模型，每個Actor內的數據獨立存在，Actor之間通過消息傳遞的形式進行交互調度，且Actor是一種高度抽象化的編程模型，非常適合於遊戲、硬件行業。

Swoole協程與信箱

得益於Swoole4.x，我們可以基於Swoole的協程與Channel快速實現一個信箱模式調度。模擬代碼如下：

use Swoole\Coroutine\Channel;
go(function (){
  //創建十個信箱通道
  $mailBoxes = [];
  for ($i = 1;$i <= 10;$i++){
    $mailBoxes[$i] = new Channel(16);
  }
  //模擬master 郵局調度,隨機像一個信箱投遞消息
  go(function ()use($mailBoxes){
    while (1){
      \co::sleep(2);
      $key = rand(1,10);
      ($mailBoxes[$key])->push(time());
    }
  });
  //模擬actor 實體消費
  for ($i = 1;$i <= 10;$i++){
    go(function ()use($mailBoxes,$i){
      while (1){
        $msg = ($mailBoxes[$i])->pop();
        echo "Actor {$i} recv msg : {$msg} \n";
      }
    });
  }
});

以上代碼執行輸出：

php test.php
Actor 8 recv msg : 1559622691
Actor 10 recv msg : 1559622693
Actor 1 recv msg : 1559622695
Actor 5 recv msg : 1559622697

協程通道每次在POP遇到無數據的時候，都會自動讓出執行權（具體可以去看Swoole協程調度）

Actor庫

基於上面的原理，我們實行了一個多進程分佈的協程Actor庫

composer require easyswoole/actor=2.x-dev

我們依賴dev庫進行測試，生產可以自己依賴stable版本

進程關係

Easyswoole的Actor模型中，存在兩組進程，一組是proxy進程，用來實現Actor對外服務，一組是worker進程，proxy進程與worker進程之間通過unixsock進行通訊，而Actor實例就均勻的分佈worker之中。

樣例代碼

比如在一個聊天室中，我們可以定義一個房間模型。

namespace EasySwoole\Actor\Test;


use EasySwoole\Actor\AbstractActor;
use EasySwoole\Actor\ActorConfig;

class RoomActor extends AbstractActor
{
  public static function configure(ActorConfig $actorConfig)
  {
    $actorConfig->setActorName('Room');
  }
  public function onStart()
  {
    //每當一個RoomActor實體被創建的時候，都會執行該回調
    var_dump('room actor '.$this->actorId().' start');
  }
  public function onMessage($msg)
  {
    //每當一個RoomActor實體收到外部消息的時候，都會執行該回調當
    var_dump('room actor '.$this->actorId().' onmessage: '.$msg);
    return 'reply at '.time();
  }
  public function onExit($arg)
  { 
    //每當一個RoomActor實體退出的時候，都會執行該回調
    var_dump('room actor '.$this->actorId().' exit at arg: '.$arg);
    return 'exit at '.time();
  }
  protected function onException(\Throwable $throwable)
  {
    //每當一個RoomActor出現異常的時候，都會執行該回調
    var_dump($throwable->getMessage());
  }
}

在cli模式下創建一個Actor服務

use EasySwoole\Actor\Actor;
use EasySwoole\Actor\Test\RoomActor;
use EasySwoole\Actor\ProxyProcess;

Actor::getInstance()->register(RoomActor::class);
$list = Actor::getInstance()->generateProcess();

foreach ($list['proxy'] as $proxy){
  /** @var ProxyProcess $proxy */
  $proxy->getProcess()->start();
}
foreach ($list['worker'] as $actors){
  foreach ($actors as $actorProcess){
    /** @var ProxyProcess $actorProcess */
    $actorProcess->getProcess()->start();
  }
}
while($ret = \Swoole\Process::wait()) {
  echo "PID={$ret['pid']}\n";
}

創建一個cli測試腳本

use EasySwoole\Actor\Actor;
use EasySwoole\Actor\Test\RoomActor;
Actor::getInstance()->register(RoomActor::class);

go(function (){
  $actorId = RoomActor::client()->create('create arg1');
  var_dump($actorId);
  \co::sleep(3);
  var_dump(RoomActor::client()->send($actorId,'this is msg'));
  \co::sleep(3);
  var_dump(RoomActor::client()->exit($actorId,'this is exit arg'));
  \co::sleep(3);
  RoomActor::client()->create('create arg2');
  \co::sleep(3);
  RoomActor::client()->create('create arg3');
  \co::sleep(3);
  var_dump(RoomActor::client()->sendAll('sendAll msg'));
  \co::sleep(3);
  var_dump(RoomActor::client()->status());
  \co::sleep(3);
  var_dump(RoomActor::client()->exitAll('sendAll exit'));
});

以上代碼執行結果如下：

服務端

php test.php 
string(40) "room actor 00101000000000000000001 start"
string(57) "room actor 00101000000000000000001 onmessage: this is msg"
string(64) "room actor 00101000000000000000001 exit at arg: this is exit arg"
string(40) "room actor 00101000000000000000002 start"
string(40) "room actor 00103000000000000000001 start"
string(57) "room actor 00101000000000000000002 onmessage: sendAll msg"
string(57) "room actor 00103000000000000000001 onmessage: sendAll msg"
string(60) "room actor 00101000000000000000002 exit at arg: sendAll exit"
string(60) "room actor 00103000000000000000001 exit at arg: sendAll exit"

客戶端

php test2.php 
string(23) "00101000000000000000001"
string(19) "reply at 1559623925"
string(18) "exit at 1559623928"
bool(true)
array(3) {
 [1]=>
 int(1)
 [2]=>
 int(0)
 [3]=>
 int(1)
}
bool(true)

更多細節可以在EasySwoole項目官網得到文檔支持 http://easyswoole.com/

喜歡EasySwoole項目的，可以給個star https://github.com/easy-swoole/easyswoole

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持神馬文庫。