yii2源码学习笔记(八）

  1 php
  2 /**
  3  * @link http://www.yiiframework.com/
  4  * @copyright Copyright (c) 2008 Yii Software LLC
  5  * @license http://www.yiiframework.com/license/
  6  */
  7 
  8 namespace yii\base;
  9 
 10 use Yii;
 11 
 12 /**
 13  * Action is the base class for all controller action classes.
 14  * 是所有控制器的基类
 15  * Action provides a way to pide a complex controller into
 16  * smaller actions in separate class files.
 17  * 控制器提供了一种重复使用操作方法的代码，在多个控制器或不同的项目中使用
 18  * Derived classes must implement a method named `run()`. This method
 19  * will be invoked by the controller when the action is requested.
 20  * The `run()` method can have parameters which will be filled up
 21  * with user input values automatically according to their names.
 22  * 派生类必须实现一个名为run()的方法，这个方法会在控制器被请求时调用。
 23  * 它可以有参数，将用户输入值的根据他们的名字自动填补。
 24  * For example, if the `run()` method is declared as follows:
 25  * 例：run()方法调用声明如下：
 26  * ~~~
 27  * public function run($id, $type = 'book') { ... }
 28  * ~~~
 29  *
 30  * And the parameters provided for the action are: `['id' => 1]`.
 31  * Then the `run()` method will be invoked as `run(1)` automatically.
 32  * 并且提供了操作的参数 ['id'=>1];
 33  * 当run(1)时自动调用run();
 34  * @property string $uniqueId The unique ID of this action among the whole application. This property is
 35  * read-only.
 36  * 整个应用程序中，这一行动的唯一标识。此属性是只读
 37  * @author Qiang Xue 
 38  * @since 2.0
 39  */
 40 class Action extends Component
 41 {
 42     /**
 43      * @var string ID of the action     ID的动作
 44      */
 45     public $id;
 46     /**
 47      * @var Controller|\yii\web\Controller the controller that owns this action
 48      * 拥有这一行动的控制器
 49      */
 50     public $controller;
 51 
 52 
 53     /**
 54      * Constructor.
 55      * 构造函数
 56      * @param string $id the ID of this action  这一行动的ID
 57      * @param Controller $controller the controller that owns this action 拥有这一行动的控制器
 58      * @param array $config name-value pairs that will be used to initialize the object properties
 59      * 用来初始化对象属性的 name-value 
 60      */
 61     public function __construct($id, $controller, $cOnfig= [])
 62     {
 63         $this->id = $id;
 64         $this->cOntroller= $controller;
 65         //调用父类的__construct()方法
 66         parent::__construct($config);
 67     }
 68 
 69     /**
 70      * Returns the unique ID of this action among the whole application.
 71      * 返回整个应用程序中的唯一ID。
 72      * @return string the unique ID of this action among the whole application.
 73      * 在整个应用程序中，这一行动的唯一ID。
 74      */
 75     public function getUniqueId()
 76     {
 77         return $this->controller->getUniqueId() . '/' . $this->id;
 78     }
 79 
 80     /**
 81      * Runs this action with the specified parameters.  用指定的参数运行此操作。
 82      * This method is mainly invoked by the controller. 该方法主要由控制器调用。
 83      *
 84      * @param array $params the parameters to be bound to the action's run() method.绑定到行动的run()方法的参数。
 85      * @return mixed the result of the action   行动的结果  命名参数是否有效的
 86      * @throws InvalidConfigException if the action class does not have a run() method
 87      * 如果动作类没有run()方法 扔出异常
 88      */
 89     public function runWithParams($params)
 90     {
 91         if (!method_exists($this, 'run')) {//如果动作类没有run()方法 抛出异常
 92             throw new InvalidConfigException(get_class($this) . ' must define a "run()" method.');
 93         }
 94         //调用bindActionParams()方法将参数绑定到动作。
 95         $args = $this->controller->bindActionParams($this, $params);
 96         //记录跟踪消息
 97         Yii::trace('Running action: ' . get_class($this) . '::run()', __METHOD__);
 98         if (Yii::$app->requestedParams === null) {
 99             //请求的动作提供的参数
100             Yii::$app->requestedParams = $args;
101         }
102         if ($this->beforeRun()) {
103             //执行run()方法
104             $result = call_user_func_array([$this, 'run'], $args);
105             $this->afterRun();
106 
107             return $result;
108         } else {
109             return null;
110         }
111     }
112 
113     /**
114      * This method is called right before `run()` is executed.
115      * ` run() `执行前方法被调用。
116      * You may override this method to do preparation work for the action run.
117      * 可以重写此方法，为该操作运行的准备工作。
118      * If the method returns false, it will cancel the action.
119      * 如果该方法返回false，取消该操作。
120      * @return boolean whether to run the action.
121      */
122     protected function beforeRun()
123     {
124         return true;
125     }
126 
127     /**
128      * This method is called right after `run()` is executed.       ` run() `执行后 方法被调用。
129      * You may override this method to do post-processing work for the action run.
130      * 可以重写此方法来处理该动作的后续处理工作。
131      */
132     protected function afterRun()
133     {
134     }
135 }

接下来我们看一下事件参数相关重要的一个类ActionEvent。yii2\base\ActionEvent.php

 1 php
 2 /**
 3  * @link http://www.yiiframework.com/
 4  * @copyright Copyright (c) 2008 Yii Software LLC
 5  * @license http://www.yiiframework.com/license/
 6  */
 7 
 8 namespace yii\base;
 9 
10 /**
11  * ActionEvent represents the event parameter used for an action event.
12  * 用于操作事件的事件参数
13  * By setting the [[isValid]] property, one may control whether to continue running the action.
14  * 通过设置[[isValid]]属性，控制是否继续运行action。
15  * @author Qiang Xue 
16  * @since 2.0
17  */
18 class ActionEvent extends Event
19 {
20     /**
21      * @var Action the action currently being executed
22      * 目前正在执行的行动
23      */
24     public $action;
25     /**
26      * @var mixed the action result. Event handlers may modify this property to change the action result.
27      * 操作结果 事件处理程序可以修改此属性来更改操作结果。
28      */
29     public $result;
30     /**
31      * @var boolean whether to continue running the action. Event handlers of
32      * [[Controller::EVENT_BEFORE_ACTION]] may set this property to decide whether
33      * to continue running the current action.
34      * 是否继续运行该动作。设置[[Controller::EVENT_BEFORE_ACTION]]属性决定是否执行当前的操作
35      */
36     public $isValid = true;
37 
38 
39     /**
40      * Constructor.构造函数。
41      * @param Action $action the action associated with this action event.与此事件相关联的动作。
42      * @param array $config name-value pairs that will be used to initialize the object properties
43      * 用来初始化对象属性的 name-value
44      */
45     public function __construct($action, $cOnfig= [])
46     {
47         $this->action = $action;
48         parent::__construct($config);
49     }
50 }

今天最后看一下操作过滤器的基类吧ActionFilter。yii2\base\ActionFilter.php。

  1 php
  2 /**
  3  * @link http://www.yiiframework.com/
  4  * @copyright Copyright (c) 2008 Yii Software LLC
  5  * @license http://www.yiiframework.com/license/
  6  */
  7 
  8 namespace yii\base;
  9 
 10 /**
 11  * ActionFilter is the base class for action filters.
 12  * 是操作过滤器的基类。
 13  * An action filter will participate in the action execution workflow by responding to
 14  * the `beforeAction` and `afterAction` events triggered by modules and controllers.
 15  * 一个操作过滤器将参与行动的执行工作流程，通过触发模型和控制器的`beforeAction` 和`afterAction` 事件
 16  * Check implementation of [[\yii\filters\AccessControl]], [[\yii\filters\PageCache]] and [[\yii\filters\HttpCache]] as examples on how to use it.
 17  * 
 18  * @author Qiang Xue 
 19  * @since 2.0
 20  */
 21 class ActionFilter extends Behavior
 22 {
 23     /**
 24      * @var array list of action IDs that this filter should apply to. If this property is not set,
 25      * then the filter applies to all actions, unless they are listed in [[except]].
 26      * 操作标识列表。如果该属性未设置，过滤器适用于所有的行动，除非它们被列入[[except]]中。
 27      * If an action ID appears in both [[only]] and [[except]], this filter will NOT apply to it.
 28      * 如果一个操作ID 出现在[[only]] 和[[except]]中，该筛选器将不适用它
 29      * Note that if the filter is attached to a module, the action IDs should also include child module IDs (if any)
 30      * and controller IDs.
 31      * 如果过滤器是链接到一个模块，操作检测还应包括子模块和控制器
 32      *
 33      * @see except
 34      */
 35     public $only;
 36     /**
 37      * @var array list of action IDs that this filter should not apply to.
 38      * 此筛选器不应适用于操作ID。
 39      * @see only
 40      */
 41     public $except = [];
 42 
 43 
 44     /**
 45      * @inheritdoc
 46      * 将行为对象附加到组件。
 47      */
 48     public function attach($owner)
 49     {
 50         $this->owner = $owner;
 51         $owner->on(Controller::EVENT_BEFORE_ACTION, [$this, 'beforeFilter']);
 52     }
 53 
 54     /**
 55      * @inheritdoc
 56      * 将行为对象和组件分离。
 57      */
 58     public function detach()
 59     {
 60         if ($this->owner) {
 61             $this->owner->off(Controller::EVENT_BEFORE_ACTION, [$this, 'beforeFilter']);
 62             $this->owner->off(Controller::EVENT_AFTER_ACTION, [$this, 'afterFilter']);
 63             $this->owner = null;
 64         }
 65     }
 66 
 67     /**
 68      * @param ActionEvent $event    在动作之前调用
 69      */
 70     public function beforeFilter($event)
 71     {
 72         if (!$this->isActive($event->action)) {
 73             return;
 74         }
 75 
 76         $event->isValid = $this->beforeAction($event->action);
 77         if ($event->isValid) {
 78             // call afterFilter only if beforeFilter succeeds    beforeFilter 执行成功调用afterFilter
 79             // beforeFilter and afterFilter should be properly nested  两者要配合应用
 80             $this->owner->on(Controller::EVENT_AFTER_ACTION, [$this, 'afterFilter'], null, false);
 81         } else {
 82             $event->handled = true;
 83         }
 84     }
 85 
 86     /**
 87      * @param ActionEvent $event
 88      */
 89     public function afterFilter($event)
 90     {
 91         $event->result = $this->afterAction($event->action, $event->result);
 92         $this->owner->off(Controller::EVENT_AFTER_ACTION, [$this, 'afterFilter']);
 93     }
 94 
 95     /**
 96      * This method is invoked right before an action is to be executed (after all possible filters.)
 97      * 此方法是在一个动作之前被调用的（
 98      * You may override this method to do last-minute preparation for the action.
 99      * @param Action $action the action to be executed.要执行的动作
100      * @return boolean whether the action should continue to be executed.
101      * 是否应继续执行该动作。
102      */
103     public function beforeAction($action)
104     {
105         return true;
106     }
107 
108     /**
109      * This method is invoked right after an action is executed.
110      * 此方法是在执行动作之后调用的。
111      * You may override this method to do some postprocessing for the action.
112      * @param Action $action the action just executed.  刚刚执行的动作
113      * @param mixed $result the action execution result 行动执行结果
114      * @return mixed the processed action result.   处理结果。
115      */
116     public function afterAction($action, $result)
117     {
118         return $result;
119     }
120 
121     /**
122      * Returns a value indicating whether the filer is active for the given action.
123      * 返回一个值，给定的过滤器的行动是否为是积极的。
124      * @param Action $action the action being filtered 被过滤的动作
125      * @return boolean whether the filer is active for the given action.
126      * 给定的过滤器的行动是否为是积极的。
127      */
128     protected function isActive($action)
129     {
130         if ($this->owner instanceof Module) {
131             // convert action uniqueId into an ID relative to the module
132             $mid = $this->owner->getUniqueId();
133             $id = $action->getUniqueId();
134             if ($mid !== '' && strpos($id, $mid) === 0) {
135                 $id = substr($id, strlen($mid) + 1);
136             }
137         } else {
138             $id = $action->id;
139         }
140         return !in_array($id, $this->except, true) && (empty($this->only) || in_array($id, $this->only, true));
141     }
142 }