workerman源码-workerman事件监听

在我们启动了workerman过后,按照我们前面的理解.如果是在linux下.worker子进程启动端口复用,并监听事件和处理事件(win忽略).那workerman是如何对事件完成监听和处理的呢.我们来看一下.

worker listen

在我们看源码的时候,在forkOneWorkerForLinux有这样一行代码.

if ($worker->reusePort) {  
 $worker->listen();}  

这里,一看名字就知道是对端口进行监听.我们来看一下源码

public function listen()  
{  
    // 这里的socketName就是我们监听的地址信息.  
    if (!$this->_socketName) { return; }  
    // 设置自动加载的信息.  
    Autoloader::setRootPath($this->_autoloadRootPath); 
    // 需要监听的socket.  
    if (!$this->_mainSocket) { 
        // 解析socket地址.  
        $local_socket = $this->parseSocketAddress();  
        // 设置基础协议.如果是udp.就为STREAM_SERVER_BIND,如果不是udp就是,就是4 | 8.注意,这里是按位或算法.则为 100(4) | 1000(8) = 1100. 
        $flags = $this->transport === 'udp' ? STREAM_SERVER_BIND : STREAM_SERVER_BIND | STREAM_SERVER_LISTEN; $errno = 0; $errmsg = ''; 
        // 设置端口复用.  
        if ($this->reusePort) {
            \stream_context_set_option($this->\context, 'socket', 'so_reuseport', 1); 
        }
        // 开始创建socket.  
        $this->_mainSocket = \stream_socket_server($local_socket, $errno, $errmsg, $flags, $this->_context); 
        if (!$this->_mainSocket) { 
            throw new Exception($errmsg); 
        } 
        // 如果transport为ssl,就要特殊处理.  
        if ($this->transport === 'ssl') { 
            \stream_socket_enable_crypto($this->_mainSocket, false); 
        } elseif ($this->transport === 'unix') { 
            // 如果是unix.  
            $socket_file = \substr($local_socket, 7); 
            if ($this->user) { 
                chown($socket_file, $this->user); 
            } 
            if ($this->group) { 
                chgrp($socket_file, $this->group); 
            } 
        }
        // 尝试打开tcp的keepalive并禁用掉Nagle算法.  
        if (\function_exists('socket_import_stream') && static::$_builtinTransports[$this->transport] === 'tcp') { 
            \set_error_handler(function(){}); 
            $socket = \socket_import_stream($this->_mainSocket); 
            \socket_set_option($socket, SOL_SOCKET, SO_KEEPALIVE, 1); 
            \socket_set_option($socket, SOL_TCP, TCP_NODELAY, 1); 
            \restore_error_handler(); 
        } // 为资源流设置为非阻塞模式.  
        \stream_set_blocking($this->_mainSocket, 0); 
    } 
    // 设置监听.  
    $this->resumeAccept();}  

在这里,workerman首先是创建了一个_mainSocket的socket监听信息.并设置为非阻塞模式.并设置监听.

public function resumeAccept()  
{  
    // 设置事件监听.  
    if (static::$globalEvent && true === $this->_pauseAccept && $this->_mainSocket) { 
        // 如果不是udp协议.就采用acceptConnection来才听.  
        if ($this->transport !== 'udp') {
            static::$globalEvent->add($this->_mainSocket, EventInterface::EV_READ, array($this, 'acceptConnection')); 
        } else { 
            // udp协议,就采用acceptUdpConnection来监听  
            static::$globalEvent->add($this->_mainSocket, EventInterface::EV_READ, array($this, 'acceptUdpConnection')); 
        } 
        // 设置pauseAccept为false.  
        $this->_pauseAccept = false; 
    }
}  

我们来看看acceptConnection.

public function acceptConnection($socket)  
{  
    // 设置错误信息.  
    \set_error_handler(function(){}); 
    // 接收信息.  
    $new_socket = stream_socket_accept($socket, 0, $remote_address); 
    // 恢复错误信息.  
    \restore_error_handler();  
    // 如果没有接收成功.  
    if (!$new_socket) { return; } 
    // 底层采用Tcp来监听.  
    $connection                         = new TcpConnection($new_socket, $remote_address); 
    // 设置connections来监听.  
    $this->connections[$connection->id] = $connection; 
    // 把worker复制进去.  
    $connection->worker                 = $this;
    $connection->protocol               = $this->protocol; 
    $connection->transport              = $this->transport; 
    // 设置事件监听.  
    $connection->onMessage              = $this->onMessage; 
    // 关闭链接时的处理.  
    $connection->onClose                = $this->onClose; 
    // 设置错误信息.  
    $connection->onError                = $this->onError; 
    $connection->onBufferDrain          = $this->onBufferDrain; 
    $connection->onBufferFull           = $this->onBufferFull;  
    // 如果有onConnect连接处理.就直接调用．  
    if ($this->onConnect) { 
        try { 
        \call_user_func($this->onConnect, $connection); 
        } catch (\Exception $e) { 
            static::log($e); 
            exit(250); 
        } catch (\Error $e) { 
            static::log($e); 
            exit(250); 
        } 
    }
}  

这里,我们就完成了对事件的监听.并且每个链接下面都将worker的信息赋值给TcpConnection的worker中.所以,每一个Connection都会有worker信息.完成了事件的监听.那如何处理事件的呢.

event loop

我们在worker的run方法中,有这样一句话.

static::$globalEvent->loop();  

这里采用了死循环来等待来处理事件.我们在前面看了.$globalEvent是采用workerman自己本身的来监听.它是在run方法中初始化的.

// run 
if (!static::$globalEvent) {  
    $event_loop_class = static::getEventLoopName(); 
    static::$globalEvent = new $event_loop_class; 
    $this->resumeAccept();
}  
  
// Worker::getEventLoopName()  
protected static function getEventLoopName()  
{  
    // 如果存在就直接返回.  
    if (static::$eventLoopClass) { 
        return static::$eventLoopClass; 
    } 
    // 如果存在就删除Swoole\Event.  
    if (!\class_exists('\Swoole\Event', false)) {
           unset(static::$_availableEventLoops['swoole']); 
    }     
    $loop_name = '';
    
    // protected static $\_availableEventLoops = array(  
    //     'libevent' => '\\Workerman\\Events\\Libevent', 
    //     'event'    => '\\Workerman\\Events\\Event'     
    //     'swoole'   => '\\Workerman\\Events\\Swoole' 
    // ); 
    foreach (static::$\_availableEventLoops as $name=>$class) { 
        if (\extension_loaded($name)) { 
            $loop_name = $name; 
            break; 
        } 
    }     
    if ($loop\_name) {  
        // 如果存在名称.就使用React下面的事件处理.  
        if  (\interface_exists('\React\EventLoop\LoopInterface')) { 
            switch ($loop_name) { 
                case 'libevent': 
                    static::$eventLoopClass = '\Workerman\Events\React\ExtLibEventLoop'; 
                    break; 
                case 'event': 
                    static::$eventLoopClass = '\Workerman\Events\React\ExtEventLoop'; 
                    break; 
                default : 
                    static::$eventLoopClass = '\Workerman\Events\React\StreamSelectLoop'; 
                    break; 
            } 
        } else { 
            // 就默认. 我们这里采用的Libevent.  
            static::$eventLoopClass = static::$\_availableEventLoops[$loop_name]; 
        } 
    } else { 
        static::$eventLoopClass = \interface_exists('\React\EventLoop\LoopInterface')? '\Workerman\Events\React\StreamSelectLoop':'\Workerman\Events\Select'; 
    } 
    return static::$eventLoopClass;
}  

以上就是初始化$globalEvent.我当前的环境是libevent.所以我们就看一下.WorkermanEventsLibevent的loop方法.

public function loop()  
{  
    // 调用了一个event_base_loop.  
    \event_base_loop($this->_eventBase);
}  

只有一个方法.event_base_loop就等待事件被触发,然后触发他们的事件.这里的是$this->_eventBase.而设置事件则在我们的add方法中.在listen的时候,我们调用了如下的方法.

static::$globalEvent->add($this->_mainSocket, EventInterface::EV_READ, array($this, 'acceptConnection'));  

所以我们来看一下add.

public function add($fd, $flag, $func, $args = array())  
{  
    // 判断信息.  
    switch ($flag) { 
        case self::EV_SIGNAL: 
            $fd_key                      = (int)$fd;               $real_flag                   = EV_SIGNAL | EV_PERSIST; 
            $this->_eventSignal[$fd_key] = event_new(); 
            if (!\event_set($this->_eventSignal[$fd_key], $fd, $real_flag, $func, null)) { 
                return false; 
            } 
            if (!\event_base_set($this->_eventSignal[$fd_key], $this->_eventBase)) { 
                return false; 
            } 
            if (!\event_add($this->_eventSignal[$fd_key])) { 
                return false; 
            } 
            return true; 
        case self::EV_TIMER: 
        case self::EV_TIMER_ONCE: 
            $event    = \event_new(); 
            $timer_id = (int)$event; 
            if (!\event_set($event, 0, EV_TIMEOUT, array($this, 'timerCallback'), $timer_id)) { 
                return false; 
            }  
            if (!\event_base_set($event, $this->_eventBase)) { 
                return false; 
            }  
            $time_interval = $fd * 1000000; 
            if (!\event_add($event, $time_interval)) { 
                return false; 
            } 
            $this->_eventTimer[$timer_id] = array($func, (array)$args, $event, $flag, $time_interval); 
            return $timer_id; 
        default : 
            $fd_key    = (int)$fd; 
            $real_flag = $flag === self::EV_READ ? EV_READ | EV_PERSIST : EV_WRITE | EV_PERSIST;  
            $event = \event_new();  
            if (!\event_set($event, $fd, $real_flag, $func, null)) { 
                return false; 
            }  
            if (!\event_base_set($event, $this->_eventBase)) { 
                return false; 
            }  
            if (!\event_add($event)) { 
                return false; 
            }  
            $this->_allEvents[$fd_key][$flag] = $event;  
            return true; 
    }
}  

我们从以上方法可以精简出大概的几个语句

// 创建一个新的事件.  
$event = \event_new();  
// 设置事件的监听.  
if (!\event_set($event, $fd, $real_flag, $func, null)) {  
    return false;
}  
// 重新设置event的绑定事件.  
if (!\event_base_set($event, $this->_eventBase)) {  
    return false;
}  
// 添加事件.  
if (!\event_add($event)) {  
    return false;
}  
// 保存到全局的事件中去.  
$this->_allEvents[$fd_key][$flag] = $event;  

所以.我们在run方法中,先设置事件的监听.然后在调用事件的处理.而完成事件的处理则是由我们worker自带的onMessage方法来处理.

最后

event_set和event_base_set的作用.  
workerman 对 worker的监控.