yii2源码学习笔记(十）

继续了解Application.

  /**
     * Registers the errorHandler component as a PHP error handler.
     * 注册errorHandler组件作为PHP错误处理函数
     * @param array $config application config  应用程序配置
     */
    protected function registerErrorHandler(&$config)
    {
        if (YII_ENABLE_ERROR_HANDLER) {// YII_ENABLE_ERROR_HANDLER在BaseYii中被定义为true
            if (!isset($config['components']['errorHandler']['class'])) {
                //$config['components']['errorHandler']['class']不存在结束运行    
                echo "Error: no errorHandler component is configured.
";
                exit(1);
            }
            //将$config['components']['errorHandler']的内容设置到了$this->_definitions['errorHandler']中
            $this->set('errorHandler', $config['components']['errorHandler']);
            unset($config['components']['errorHandler']);// 删除掉配置内容
            $this->getErrorHandler()->register();
        }
    }

    /**
     * Returns an ID that uniquely identifies this module among all modules within the current application.
     * Since this is an application instance, it will always return an empty string.
     * 返回在当前应用程序中该模块的唯一标识。这是一个应用实例，它将返回一个空字符串。
     * @return string the unique ID of the module.模块的唯一标识。
     */
    public function getUniqueId()
    {
        return '';
    }

    /**
     * Sets the root directory of the application and the @app alias.设置应用程序的根目录 @ 加应用程序别名。
     * This method can only be invoked at the beginning of the constructor.只能在构造函数开始时调用该方法
     * @param string $path the root directory of the application.应用程序的根目录。
     * @property string the root directory of the application. 应用程序的根目录。
     * @throws InvalidParamException if the directory does not exist. 如果目录不存在。抛出异常
     */
    public function setBasePath($path)
    {
        parent::setBasePath($path);
        // 使用@app来记录basePath
        Yii::setAlias('@app', $this->getBasePath());
    }

    /**
     * Runs the application.    运行应用程序。
     * This is the main entrance of an application. 应用程序的主要入口。
     * @return integer the exit status (0 means normal, non-zero values mean abnormal) 状态（0正常，非0为不正常）
     */
    public function run()
    {
        try {

            $this->state = self::STATE_BEFORE_REQUEST; 
            $this->trigger(self::EVENT_BEFORE_REQUEST);//加载事件函数beforRequest函数

            $this->state = self::STATE_HANDLING_REQUEST;
            $response = $this->handleRequest($this->getRequest());//加载控制器  获取Request对象

            $this->state = self::STATE_AFTER_REQUEST;
            $this->trigger(self::EVENT_AFTER_REQUEST);//加载afterRequest事件函数

            $this->state = self::STATE_SENDING_RESPONSE;
            $response->send();//将页面内容输入缓冲，然后输出

            $this->state = self::STATE_END;

            return $response->exitStatus;

        } catch (ExitException $e) {
            
            $this->end($e->statusCode, isset($response) ? $response : null);
            return $e->statusCode;

        }
    }

    /**
     * Handles the specified request.
     *  处理指定的请求
     * This method should return an instance of [[Response]] or its child class
     * which represents the handling result of the request.
     *  该方法应该返回一个[[Response]]实例，或者它的子类代表处理请求的结果
     * @param Request $request the request to be handled    被处理的请求
     * @return Response the resulting response  得到的响应
     */
    abstract public function handleRequest($request);

    private $_runtimePath;

    /**
     * Returns the directory that stores runtime files.返回存储运行时文件的路径
     * @return string the directory that stores runtime files.存储运行时文件的目录。
     * Defaults to the "runtime" subdirectory under [[basePath]].默认返回[[basePath]]下的 "runtime"目录
     */
    public function getRuntimePath()
    {
        if ($this->_runtimePath === null) {//设置临时文件存储路径
            $this->setRuntimePath($this->getBasePath() . DIRECTORY_SEPARATOR . 'runtime');
        }

        return $this->_runtimePath;
    }

    /**
     * Sets the directory that stores runtime files.设置存储运行时文件的路径
     * @param string $path the directory that stores runtime files.存储运行时文件的目录。
     */
    public function setRuntimePath($path)
    {
        // 获取runtimePath的路径，并存到_runtimePath中
        $this->_runtimePath = Yii::getAlias($path);
         // 使用@runtime来记录 runtimePath
        Yii::setAlias('@runtime', $this->_runtimePath);
    }

    private $_vendorPath;

    /**
     * Returns the directory that stores vendor files.返回插件文件的目录。
     * @return string the directory that stores vendor files.
     * Defaults to "vendor" directory under [[basePath]].
     * 默认返回[[basePath]]下的 "vendor" 目录
     */
    public function getVendorPath()
    {
        if ($this->_vendorPath === null) {
            // 不存在，就将其设置为basePath/vendor
            $this->setVendorPath($this->getBasePath() . DIRECTORY_SEPARATOR . 'vendor');
        }

        return $this->_vendorPath;
    }

    /**
     * Sets the directory that stores vendor files.设置插件目录路径，并设置别名
     * @param string $path the directory that stores vendor files.
     */
    public function setVendorPath($path)
    {
        $this->_vendorPath = Yii::getAlias($path);// 获取vendor的路径，并存到_vendorPath中
        Yii::setAlias('@vendor', $this->_vendorPath);// 设置@vendor的alias
        Yii::setAlias('@bower', $this->_vendorPath . DIRECTORY_SEPARATOR . 'bower');
        Yii::setAlias('@npm', $this->_vendorPath . DIRECTORY_SEPARATOR . 'npm');
    }

    /**
     * Returns the time zone used by this application.取得时区
     * This is a simple wrapper of PHP function date_default_timezone_get().
     * If time zone is not configured in php.ini or application config,
     * it will be set to UTC by default.
     * @return string the time zone used by this application.
     * @see http://php.net/manual/en/function.date-default-timezone-get.php
     */
    public function getTimeZone()
    {
        return date_default_timezone_get();
    }

    /**
     * Sets the time zone used by this application.设置时区
     * This is a simple wrapper of PHP function date_default_timezone_set().
     * Refer to the [php manual](http://www.php.net/manual/en/timezones.php) for available timezones.
     * @param string $value the time zone used by this application.
     * @see http://php.net/manual/en/function.date-default-timezone-set.php
     */
    public function setTimeZone($value)
    {
        date_default_timezone_set($value);
    }

    /**
     * Returns the database connection component.返回数据库连接组件
     * @return yiidbConnection the database connection.
     */
    public function getDb()
    {
        return $this->get('db');
    }

    /**
     * Returns the log dispatcher component.返回日志调度组件
     * @return yiilogDispatcher the log dispatcher application component.
     */
    public function getLog()
    {
        return $this->get('log');
    }

    /**
     * Returns the error handler component.返回错误处理组件
     * @return yiiwebErrorHandler|yiiconsoleErrorHandler the error handler application component.
     */
    public function getErrorHandler()
    {
        return $this->get('errorHandler');
    }

    /**
     * Returns the cache component.返回缓存组件
     * @return yiicachingCache the cache application component. Null if the component is not enabled.
     */
    public function getCache()
    {
        return $this->get('cache', false);
    }

    /**
     * Returns the formatter component.返回格式化程序组件
     * @return yiii18nFormatter the formatter application component.
     */
    public function getFormatter()
    {
        return $this->get('formatter');
    }

    /**
     * Returns the request component.返回请求的组件对象
     * @return yiiwebRequest|yiiconsoleRequest the request component.
     */
    public function getRequest()
    {
        return $this->get('request');
    }

    /**
     * Returns the response component.返回响应组件
     * @return yiiwebResponse|yiiconsoleResponse the response component.
     */
    public function getResponse()
    {
        return $this->get('response');
    }

    /**
     * Returns the view object.返回视图对象
     * @return View|yiiwebView the view application component that is used to render various view files.
     */
    public function getView()
    {
        return $this->get('view');
    }

    /**
     * Returns the URL manager for this application.返回当前应用的URL管理组件
     * @return yiiwebUrlManager the URL manager for this application.
     */
    public function getUrlManager()
    {
        return $this->get('urlManager');
    }

    /**
     * Returns the internationalization (i18n) component返回国际化组件
     * @return yiii18nI18N the internationalization application component.
     */
    public function getI18n()
    {
        return $this->get('i18n');
    }

    /**
     * Returns the mailer component.返回邮件组件
     * @return yiimailMailerInterface the mailer application component.
     */
    public function getMailer()
    {
        return $this->get('mailer');
    }

    /**
     * Returns the auth manager for this application.返回该应用的权限管理组件
     * @return yii
bacManagerInterface the auth manager application component.
     * Null is returned if auth manager is not configured.   管理权限没有配置返回null
     */
    public function getAuthManager()
    {
        return $this->get('authManager', false);
    }

    /**
     * Returns the asset manager.返回资源管理组件
     * @return yiiwebAssetManager the asset manager application component.
     */
    public function getAssetManager()
    {
        return $this->get('assetManager');
    }

    /**
     * Returns the security component.返回安全组件
     * @return yiiaseSecurity the security application component.
     */
    public function getSecurity()
    {
        return $this->get('security');
    }

    /**
     * Returns the configuration of core application components.返回核心组件的配置
     * @see set()
     */
    public function coreComponents()
    {
        return [
            'log' => ['class' => 'yiilogDispatcher'],
            'view' => ['class' => 'yiiwebView'],
            'formatter' => ['class' => 'yiii18nFormatter'],
            'i18n' => ['class' => 'yiii18nI18N'],
            'mailer' => ['class' => 'yiiswiftmailerMailer'],
            'urlManager' => ['class' => 'yiiwebUrlManager'],
            'assetManager' => ['class' => 'yiiwebAssetManager'],
            'security' => ['class' => 'yiiaseSecurity'],
        ];
    }

    /**
     * Terminates the application.终止应用程序
     * This method replaces the `exit()` function by ensuring the application life cycle is completed
     * before terminating the application.该方法代替`exit()`  确认一个应用的生命周期已经结束
     * @param integer $status the exit status (value 0 means normal exit while other values mean abnormal exit).
     * @param Response $response the response to be sent. If not set, the default application [[response]] component will be used.
     * @throws ExitException if the application is in testing mode
     */
    public function end($status = 0, $response = null)
    {
        if ($this->state === self::STATE_BEFORE_REQUEST || $this->state === self::STATE_HANDLING_REQUEST) {
            //判断当前状态为请求前或者处理请求
            $this->state = self::STATE_AFTER_REQUEST;//设置应用状态为请求完成后
            $this->trigger(self::EVENT_AFTER_REQUEST);
        }

        if ($this->state !== self::STATE_SENDING_RESPONSE && $this->state !== self::STATE_END) {
            //如果应用状态不是发送应答和应用结束
            $this->state = self::STATE_END;//设置状态为应用结束
            $response = $response ? : $this->getResponse();
            $response->send();//向客户端发送应答
        }

        if (YII_ENV_TEST) {
            throw new ExitException($status);
        } else {
            exit($status);
        }
    }

php