【zendframework】引导程序

zendFramework引导过程通过Application组件完成，由于是对老版本的兼容扩展，其实现起来感觉没有yii那样优雅，它把类库当做资源，而原来那些类库又没有统一的接口，因此又需要新写资源类来间接配置和获取相应的资源。

Zend_Application

zendFramework配置的加载通过入口文件实例Zend_Application来完成，构造方法通过初始化配置后，通过setOptions方法来加载应用的配置。在配置中主要有phpsettings、includepaths、autoloadernamespaces、autoloaderzfpath、bootstrap、appnamespace、resources等。

 public function setOptions(array $options)
 {
     if (!empty($options['config'])) {
         if (is_array($options['config'])) {
             $_options = array();
             foreach ($options['config'] as $tmp) {
                 $_options = $this->mergeOptions($_options, $this->_loadConfig($tmp));
             }
             $options = $this->mergeOptions($_options, $options);
         } else {
             $options = $this->mergeOptions($this->_loadConfig($options['config']), $options);
         }
     }

     $this->_options = $options;

     $options = array_change_key_case($options, CASE_LOWER);
     $this->_optionKeys = array_keys($options);
     if (!empty($options['phpsettings'])) {
         $this->setPhpSettings($options['phpsettings']);
     }

     if (!empty($options['includepaths'])) {
         $this->setIncludePaths($options['includepaths']);
     }

     if (!empty($options['autoloadernamespaces'])) {
         $this->setAutoloaderNamespaces($options['autoloadernamespaces']);
     }

     if (!empty($options['autoloaderzfpath'])) {
         $autoloader = $this->getAutoloader();
         if (method_exists($autoloader, 'setZfPath')) {
             $zfPath    = $options['autoloaderzfpath'];
             $zfVersion = !empty($options['autoloaderzfversion'])
                         ? $options['autoloaderzfversion']
                         : 'latest';
             $autoloader->setZfPath($zfPath, $zfVersion);
         }
     }

     if (!empty($options['bootstrap'])) {
         $bootstrap = $options['bootstrap'];

         if (is_string($bootstrap)) {
             $this->setBootstrap($bootstrap);
         } elseif (is_array($bootstrap)) {
             if (empty($bootstrap['path'])) {
                 throw new Zend_Application_Exception('No bootstrap path provided');
             }

             $path  = $bootstrap['path'];
             $class = null;

             if (!empty($bootstrap['class'])) {
                 $class = $bootstrap['class'];
             }
             $this->setBootstrap($path, $class);
         } else {
             throw new Zend_Application_Exception('Invalid bootstrap information provided');
         }
     }

     return $this;
 }

Bootstrap

在zf应用中，把框架中类库的看做资源，配置中以resources开头的都是资源相关配置，如resources.frontController.controllerDirectory = APPLICATION_PATH "/controllers"配置控制器所在的目录。Zend_Application通过配置实例化Bootstrap来配置资源。

 public function setOptions(array $options)
 {
     $this->_options = $this->mergeOptions($this->_options, $options);

     $options = array_change_key_case($options, CASE_LOWER);
     $this->_optionKeys = array_merge($this->_optionKeys, array_keys($options));

     $methods = get_class_methods($this);

     foreach ($methods as $key => $method) {
         $methods[$key] = strtolower($method);
     }

     if (array_key_exists('pluginpaths', $options)) {
         $pluginLoader = $this->getPluginLoader();

         foreach ($options['pluginpaths'] as $prefix => $path) {
             $pluginLoader->addPrefixPath($prefix, $path);
         }
         unset($options['pluginpaths']);
     }

     foreach ($options as $key => $value) {

         $method = 'set' . strtolower($key);

         if (in_array($method, $methods)) {
             $this->$method($value);
         } elseif ('resources' == $key) {
             foreach ($value as $resource => $resourceOptions) {
                 $this->registerPluginResource($resource, $resourceOptions);
             }
         }
     }
     return $this;
 }

配置加载好后，需要启动支持程序运行的，在_bootstrap()首先通过中getClassResourceNames()将获捕获导类中以_init开头的方法，这些方法是通过在引导类内部配置相关资源，然后获取配置中的资源并执行引导，在执行引导的时候会把资源注册在一个全局容器中，通过getResource($resource)方法可以获取容器中的资源。

 /**
   * 获取内部和外部配置资源并执行
   */
 protected function _bootstrap($resource = null)
 {

     if (null === $resource) {
         //引导类内部方法
         foreach ($this->getClassResourceNames() as $resource) {
             $this->_executeResource($resource);
         }
         //配置中的资源
         foreach ($this->getPluginResourceNames() as $resource) {
             $this->_executeResource($resource);
         }

     } elseif (is_string($resource)) {
         $this->_executeResource($resource);
     } elseif (is_array($resource)) {
         foreach ($resource as $r) {
             $this->_executeResource($r);
         }
     } else {
         throw new Zend_Application_Bootstrap_Exception('Invalid argument passed to ' . __METHOD__);
     }
 }
 /**
   * Execute a resource 执行资源并注册全局资源实例
   */
 protected function _executeResource($resource)
 {
     $resourceName = strtolower($resource);
     if (in_array($resourceName, $this->_run)) {
         return;
     }

     if (isset($this->_started[$resourceName]) && $this->_started[$resourceName]) {
         throw new Zend_Application_Bootstrap_Exception('Circular resource dependency detected');
     }

     $classResources = $this->getClassResources();

     if (array_key_exists($resourceName, $classResources)) {
         $this->_started[$resourceName] = true;
         $method = $classResources[$resourceName];
         $return = $this->$method();
         unset($this->_started[$resourceName]);
         $this->_markRun($resourceName);

         if (null !== $return) {
             $this->getContainer()->{$resourceName} = $return;
         }

         return;
     }

     if ($this->hasPluginResource($resource)) {
         $this->_started[$resourceName] = true;
         $plugin = $this->getPluginResource($resource);

         $return = $plugin->init();
         unset($this->_started[$resourceName]);
         $this->_markRun($resourceName);

         if (null !== $return) {
             $this->getContainer()->{$resourceName} = $return;
         }

         return;
     }

     throw new Zend_Application_Bootstrap_Exception('Resource matching "' . $resource . '" not found');
 }

引导程序加载完成后，通过run()方法，获取前端控制器，然后前端控制器执行对请求的应答过程。