yii2源码学习笔记(九）

  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  * Application is the base class for all application classes.
 14  * 是所有应用程序类的基类
 15  * @property \yii\web\AssetManager $assetManager The asset manager application component. This property is
 16  * read-only.资产管理器应用组件，只读
 17  * @property \yii\rbac\ManagerInterface $authManager The auth manager application component. Null is returned
 18  * if auth manager is not configured. This property is read-only.认证管理器应用程序组件。未配置返回null，只读
 19  * @property string $basePath The root directory of the application. 应用程序的根目录。
 20  * @property \yii\caching\Cache $cache The cache application component. Null if the component is not enabled.
 21  * This property is read-only.缓存应用程序组件。
 22  * @property \yii\db\Connection $db The database connection. This property is read-only.数据库连接。
 23  * @property \yii\web\ErrorHandler|\yii\console\ErrorHandler $errorHandler The error handler application
 24  * component. This property is read-only.错误处理程序应用程序组件
 25  * @property \yii\i18n\Formatter $formatter The formatter application component. This property is read-only.
 26  * 格式化程序的应用程序组件。
 27  * @property \yii\i18n\I18N $i18n The internationalization application component. This property is read-only.
 28  * 国际化应用组件。
 29  * @property \yii\log\Dispatcher $log The log dispatcher application component. This property is read-only.
 30  * 日志调度程序组件。
 31  * @property \yii\mail\MailerInterface $mailer The mailer application component. This property is read-only.
 32  * 邮件应用程序组件。
 33  * @property \yii\web\Request|\yii\console\Request $request The request component. This property is read-only.
 34  * 请求组件。
 35  * @property \yii\web\Response|\yii\console\Response $response The response component. This property is
 36  * read-only.反应元件。
 37  * @property string $runtimePath The directory that stores runtime files. Defaults to the "runtime"
 38  * subdirectory under [[basePath]].存储运行时文件的目录。
 39  * @property \yii\base\Security $security The security application component. This property is read-only.
 40  * 安全应用组件。
 41  * @property string $timeZone The time zone used by this application.该应用程序使用的时区。
 42  * @property string $uniqueId The unique ID of the module. This property is read-only.模块的唯一标识。
 43  * @property \yii\web\UrlManager $urlManager The URL manager for this application. This property is read-only.
 44  * 此应用程序的网址管理器。
 45  * @property string $vendorPath The directory that stores vendor files. Defaults to "vendor" directory under
 46  * [[basePath]].存储供应商文件的目录。
 47  * @property View|\yii\web\View $view The view application component that is used to render various view
 48  * files. This property is read-only.用于呈现各种视图文件的视图应用程序组件
 49  *
 50  * @author Qiang Xue 
 51  * @since 2.0
 52  */
 53 abstract class Application extends Module
 54 {
 55     /**
 56      * @event Event an event raised before the application starts to handle a request.
 57      * 在应用程序开始处理请求之前提出的事件。
 58      */
 59     const EVENT_BEFORE_REQUEST = 'beforeRequest';
 60     /**
 61      * @event Event an event raised after the application successfully handles a request (before the response is sent out).
 62      * 该应用程序成功处理请求后提出的事件
 63      */
 64     const EVENT_AFTER_REQUEST = 'afterRequest';
 65     /**
 66      * Application state used by [[state]]: application just started.
 67      * [[state]]适用状态：刚开始应用
 68      */
 69     const STATE_BEGIN = 0;
 70     /**
 71      * Application state used by [[state]]: application is initializing.
 72      *  [[state]]应用程序状态：应用程序初始化。
 73      */
 74     const STATE_INIT = 1;
 75     /**
 76      * Application state used by [[state]]: application is triggering [[EVENT_BEFORE_REQUEST]].
 77      *  [[state]]应用程序状态：应用触发[[EVENT_BEFORE_REQUEST]]
 78      */
 79     const STATE_BEFORE_REQUEST = 2;
 80     /**
 81      * Application state used by [[state]]: application is handling the request.
 82      *  [[state]]应用程序状态：应用程序处理请求。
 83      */
 84     const STATE_HANDLING_REQUEST = 3;
 85     /**
 86      * Application state used by [[state]]: application is triggering [[EVENT_AFTER_REQUEST]]..
 87      *  [[state]]应用程序状态：应用触发[[EVENT_AFTER_REQUEST]]
 88      */
 89     const STATE_AFTER_REQUEST = 4;
 90     /**
 91      * Application state used by [[state]]: application is about to send response.
 92      *  [[state]]应用程序状态：应用程序即将发送响应。
 93      */
 94     const STATE_SENDING_RESPOnSE= 5;
 95     /**
 96      * Application state used by [[state]]: application has ended.
 97      *  [[state]]应用程序状态：应用程序结束。
 98      */
 99     const STATE_END = 6;
100 
101     /**
102      * @var string the namespace that controller classes are located in.控制器类的命名空间位置。
103      * This namespace will be used to load controller classes by prepending it to the controller class name.
104      * The default namespace is `app\controllers`.
105      * 此命名空间将用于负载控制器类重写它的控制器类的名字。 默认命名空间是`app\controllers`。
106      * Please refer to the [guide about class autoloading](guide:concept-autoloading.md) for more details.
107      */
108     public $cOntrollerNamespace= 'app\\controllers';
109     /**
110      * @var string the application name.应用程序名称。
111      */
112     public $name = 'My Application';
113     /**
114      * @var string the version of this application.此应用程序的版本。
115      */
116     public $version = '1.0';
117     /**
118      * @var string the charset currently used for the application.目前使用的字符集。
119      */
120     public $charset = 'UTF-8';
121     /**
122      * @var string the language that is meant to be used for end users. It is recommended that you
123      * use [IETF language tags](http://en.wikipedia.org/wiki/IETF_language_tag). For example, `en` stands
124      * for English, while `en-US` stands for English (United States).
125      * 用来作为终端用户使用的语言
126      * @see sourceLanguage
127      */
128     public $language = 'en-US';
129     /**
130      * @var string the language that the application is written in. This mainly refers to
131      * the language that the messages and view files are written in.
132      * 应用程序编写的语言。
133      * @see language
134      */
135     public $sourceLanguage = 'en-US';
136     /**
137      * @var Controller the currently active controller instance当前活动控制器实例
138      */
139     public $controller;
140     /**
141      * @var string|boolean the layout that should be applied for views in this application. Defaults to 'main'.
142      * If this is false, layout will be disabled.
143      * 该应用程序中应用的布局。
144      */
145     public $layout = 'main';
146     /**
147      * @var string the requested route请求的路径    请求的路径
148      */
149     public $requestedRoute;
150     /**
151      * @var Action the requested Action. If null, it means the request cannot be resolved into an action.
152      * 操作所要求的行动
153      */
154     public $requestedAction;
155     /**
156      * @var array the parameters supplied to the requested action.
157      * 所请求的动作提供的参数。
158      */
159     public $requestedParams;
160     /**
161      * @var array list of installed Yii extensions. Each array element represents a single extension
162      * with the following structure:
163      * 安装Yii扩展名列表。每个数组元素代表一个扩展
164      *
165      * ~~~
166      * [
167      *     'name' => 'extension name',
168      *     'version' => 'version number',
169      *     'bootstrap' => 'BootstrapClassName',  // optional, may also be a configuration array
170      *     'alias' => [
171      *         '@alias1' => 'to/path1',
172      *         '@alias2' => 'to/path2',
173      *     ],
174      * ]
175      * ~~~
176      *
177      * The "bootstrap" class listed above will be instantiated during the application
178      * [[bootstrap()|bootstrapping process]]. If the class implements [[BootstrapInterface]],
179      * its [[BootstrapInterface::bootstrap()|bootstrap()]] method will be also be called.
180      *
181      * If not set explicitly in the application config, this property will be populated with the contents of
182      * 如果在应用程序配置中没有设置，该属性将填充到内容
183      * @vendor/yiisoft/extensions.php`.
184      */
185     public $extensions;
186     /**
187      * @var array list of components that should be run during the application [[bootstrap()|bootstrapping process]].
188      * 组件的列表，运行在 [[bootstrap()|bootstrapping process]]中的应用
189      * Each component may be specified in one of the following formats:
190      *
191      * - an application component ID as specified via [[components]].
192      * - a module ID as specified via [[modules]].
193      * - a class name.
194      * - a configuration array.
195      *
196      * During the bootstrapping process, each component will be instantiated. If the component class
197      * implements [[BootstrapInterface]], its [[BootstrapInterface::bootstrap()|bootstrap()]] method
198      * will be also be called.
199      * 在整个启动过程中，每个组件被实例化。如果组件类提到 [[BootstrapInterface]]， 
200      * [[BootstrapInterface::bootstrap()|bootstrap()]]方法也会调用
201      */
202     public $bootstrap = [];
203     /**
204      * @var integer the current application state during a request handling life cycle.
205      * This property is managed by the application. Do not modify this property.    
206      * 在请求处理生命周期中的当前应用程序状态。属性由应用程序管理。不要修改此属性。
207      */
208     public $state;
209     /**
210      * @var array list of loaded modules indexed by their class names.
211      * 加载模块列表由它们的类名称索引组成。
212      */
213     public $loadedModules = [];
214 
215 
216     /**
217      * Constructor.构造函数
218      * @param array $config name-value pairs that will be used to initialize the object properties.
219      * Note that the configuration must contain both [[id]] and [[basePath]].
220      * 用来初始化对象属性的 name-value 注意配置必须包含[[id]] 和[[basePath]].
221      * @throws InvalidConfigException if either [[id]] or [[basePath]] configuration is missing.
222      * 如果是修改[[id]] 或[[basePath]] 则配置丢失。
223      */
224     public function __construct($cOnfig= [])
225     {
226         Yii::$app = $this;// 将自身的实例绑到Yii的$app上
227         $this->setInstance($this);// 将自身加入到loadedModules中
228 
229         $this->state = self::STATE_BEGIN;// 设置状态为刚开始
230 
231         // 做预处理配置
232         $this->preInit($config);
233 
234         $this->registerErrorHandler($config);
235 
236         Component::__construct($config);
237     }
238 
239     /**
240      * Pre-initializes the application. 初始化应用。
241      * This method is called at the beginning of the application constructor.
242      * It initializes several important application properties.
243      * 在构造函数中调用该方法，用于初始化一些重要的属性
244      * If you override this method, please make sure you call the parent implementation.
245      * @param array $config the application configuration   应用的配置
246      * @throws InvalidConfigException if either [[id]] or [[basePath]] configuration is missing.
247      */
248     public function preInit(&$config)
249     {
250          // 使用了&符号，表示$config的修改会保留
251         if (!isset($config['id'])) {//判断配置中是否有application ID ，如果没有，抛出异常
252             throw new InvalidConfigException('The "id" configuration for the Application is required.');
253         }
254         if (isset($config['basePath'])) {
255             // 是否配置项目的root路径
256             $this->setBasePath($config['basePath']);
257              //赋值给模块的_basepath属性，并在设置后删除
258             unset($config['basePath']);
259         } else {//否则抛出异常
260             throw new InvalidConfigException('The "basePath" configuration for the Application is required.');
261         }
262         //如果配置文件中设置了 vendorPath 使用配置的值，并在设置后删除，否则使用默认的
263         if (isset($config['vendorPath'])) {
264             $this->setVendorPath($config['vendorPath']);
265             unset($config['vendorPath']);
266         } else {
267             // set "@vendor"
268             $this->getVendorPath();
269         }
270         //如果配置文件中设置了 runtimePath 使用配置的值，并在设置后删除，否则使用默认的
271         if (isset($config['runtimePath'])) {
272             $this->setRuntimePath($config['runtimePath']);
273             unset($config['runtimePath']);
274         } else {
275             // set "@runtime"
276             $this->getRuntimePath();
277         }
278          //如果配置文件中设置了 timeZone 使用配置的值，并在设置后删除，否则使用默认的时区
279         if (isset($config['timeZone'])) {
280             $this->setTimeZone($config['timeZone']);
281             unset($config['timeZone']);
282         } elseif (!ini_get('date.timezone')) {
283             $this->setTimeZone('UTC');
284         }
285 
286         // merge core components with custom components
287         foreach ($this->coreComponents() as $id => $component) {
288             if (!isset($config['components'][$id])) {
289                 // 如果配置中没有配置相应的核心component，就赋给它
290                 $config['components'][$id] = $component;
291             } elseif (is_array($config['components'][$id]) && !isset($config['components'][$id]['class'])) {
292                  // 如果存在相应的核心component，但没有定义它的class，就直接赋到class的key上
293                 $config['components'][$id]['class'] = $component['class'];
294             }
295         }
296     }
297 
298     /**
299      * @inheritdoc
300      */
301     public function init()
302     {
303         $this->state = self::STATE_INIT;
304         $this->bootstrap();
305     }
306 
307     /**
308      * Initializes extensions and executes bootstrap components.初始化扩展并执行初始化程序组件
309      * This method is called by [[init()]] after the application has been fully configured.
310      * 该方法在应用完全配置后被[[init()]]调用
311      * If you override this method, make sure you also call the parent implementation.
312      */
313     protected function bootstrap()
314     {
315         if ($this->extensiOns=== null) {//如果没有配置，则调用Yii的默认扩展组件
316             $file = Yii::getAlias('@vendor/yiisoft/extensions.php');
317             $this->extensiOns= is_file($file) ? include($file) : [];
318         }
319         foreach ($this->extensions as $extension) {
320             if (!empty($extension['alias'])) {//如果扩展组件有设置别名
321                 foreach ($extension['alias'] as $name => $path) {
322                     Yii::setAlias($name, $path);//将给扩展的别名注册到别名数组中
323                 }
324             }
325             if (isset($extension['bootstrap'])) {//如果扩展组件有[[bootstrap]]配置 则初始化给扩展组件
326                 $compOnent= Yii::createObject($extension['bootstrap']);
327                 if ($component instanceof BootstrapInterface) {
328                     Yii::trace("Bootstrap with " . get_class($component) . '::bootstrap()', __METHOD__);
329                     $component->bootstrap($this);
330                 } else {
331                     Yii::trace("Bootstrap with " . get_class($component), __METHOD__);
332                 }
333             }
334         }
335 
336         foreach ($this->bootstrap as $class) {
337             $compOnent= null;
338             if (is_string($class)) {
339                 if ($this->has($class)) {
340                     $compOnent= $this->get($class);
341                 } elseif ($this->hasModule($class)) {
342                     $compOnent= $this->getModule($class);
343                 } elseif (strpos($class, '\\') === false) {
344                     throw new InvalidConfigException("Unknown bootstrapping component ID: $class");
345                 }
346             }
347             if (!isset($component)) {//如果不存在，则调用Yii创建对象
348                 $compOnent= Yii::createObject($class);
349             }
350 
351             if ($component instanceof BootstrapInterface) {
352                 Yii::trace("Bootstrap with " . get_class($component) . '::bootstrap()', __METHOD__);
353                 $component->bootstrap($this);
354             } else {
355                 Yii::trace("Bootstrap with " . get_class($component), __METHOD__);
356             }
357         }
358     }

未完待续。