如今來分析路由實現及執行過程,在項目目錄下建立index.php,使用文檔中的路由例子(含有路由規則匹配),以下:php
<?php require 'flight/Flight.php'; Flight::route('/@name/@id:[0-9]{3}', function($name, $id){ echo "hello, $name ($id)!"; }); Flight::start();
首先引入'flight/Flight.php'
框架入口文件,在執行Flight::route()
時固然在Flight類中找不到該方法,因而就會調用下面的__callStatic()
魔術方法,而後去執行\flight\core\Dispatcher::invokeMethod(array($app, $name), $params)
,其中$app
就是以前框架初始化好後的Engine類實例化對象,$params
就是定義路由傳入的參數:匹配規則或url和一個匿名回調函數。ajax
/** * Handles calls to static methods. * * @param string $name Method name * @param array $params Method parameters * @return mixed Callback results * @throws \Exception */ public static function __callStatic($name, $params) { $app = Flight::app(); return \flight\core\Dispatcher::invokeMethod(array($app, $name), $params); }
接着會調用Dispatcher類的invokeMethod()
方法,$class
和$method
分別對應剛纔的$app
對象和$name
參數。is_object($class)
返回true
,很明顯count($params)
值爲2,所以會執行case語句中的$class->$method($params[0], $params[1])
,就是去Engine對象中調用route()方法。segmentfault
/** * Invokes a method. * * @param mixed $func Class method * @param array $params Class method parameters * @return mixed Function results */ public static function invokeMethod($func, array &$params = array()) { list($class, $method) = $func; $instance = is_object($class); switch (count($params)) { case 0: return ($instance) ? $class->$method() : $class::$method(); case 1: return ($instance) ? $class->$method($params[0]) : $class::$method($params[0]); case 2: return ($instance) ? $class->$method($params[0], $params[1]) : $class::$method($params[0], $params[1]); case 3: return ($instance) ? $class->$method($params[0], $params[1], $params[2]) : $class::$method($params[0], $params[1], $params[2]); case 4: return ($instance) ? $class->$method($params[0], $params[1], $params[2], $params[3]) : $class::$method($params[0], $params[1], $params[2], $params[3]); case 5: return ($instance) ? $class->$method($params[0], $params[1], $params[2], $params[3], $params[4]) : $class::$method($params[0], $params[1], $params[2], $params[3], $params[4]); default: return call_user_func_array($func, $params); } }
固然在Engine對象中也沒有route()
方法,因而會觸發當前對象中的__call()
魔術方法。在這個方法中經過$this->dispatcher->get($name)
去獲取框架初始化時設置的Dispatcher對象的$events
屬性:$this->dispatcher->set($name, array($this, '_'.$name))
,而後$events
屬性數組中會有一個route
鍵名對應的值爲[$this Engine對象, '_route']
數組,返回的$callback=[$this Engine對象, '_route']
而且is_callable($callback)==true
。數組
/** * Handles calls to class methods. * * @param string $name Method name * @param array $params Method parameters * @return mixed Callback results * @throws \Exception */ public function __call($name, $params) { $callback = $this->dispatcher->get($name); if (is_callable($callback)) { return $this->dispatcher->run($name, $params); } if (!$this->loader->get($name)) { throw new \Exception("{$name} must be a mapped method."); } $shared = (!empty($params)) ? (bool)$params[0] : true; return $this->loader->load($name, $shared); }
那麼,接着就該執行$this->dispatcher->run($name, $params)
,那就看下Dispatcher對象中的run()
方法,因爲框架初始化時沒有對route()
方法進行設置前置和後置操做,因此直接執行$this->execute($this->get($name), $params)
。cookie
/** * Dispatches an event. * * @param string $name Event name * @param array $params Callback parameters * @return string Output of callback * @throws \Exception */ public function run($name, array $params = array()) { $output = ''; // Run pre-filters if (!empty($this->filters[$name]['before'])) { $this->filter($this->filters[$name]['before'], $params, $output); } // Run requested method $output = $this->execute($this->get($name), $params); // Run post-filters if (!empty($this->filters[$name]['after'])) { $this->filter($this->filters[$name]['after'], $params, $output); } return $output; }
接着來看Dispatcher對象中的execute方法,由於is_callable($callback)==true && is_array($callback)
,因此又再次調用self::invokeMethod($callback, $params)
。app
/** * Executes a callback function. * * @param callback $callback Callback function * @param array $params Function parameters * @return mixed Function results * @throws \Exception */ public static function execute($callback, array &$params = array()) { if (is_callable($callback)) { return is_array($callback) ? self::invokeMethod($callback, $params) : self::callFunction($callback, $params); } else { throw new \Exception('Invalid callback specified.'); } }
可是此次調用invokeMethod方法跟剛纔有所不一樣,剛纔的$callback是[$app, 'route']
,如今的$callback
是[$this Engine對象, '_route']
,$params
是同樣的。而後invokeMethod方法中的$class
爲$this Engine對象
,$method
爲'_route',is_object($class)
爲true。而後再執行$class->$method($params[0], $params[1])
,此次在Engine對象中就能夠調用到_route方法了。框架
接着來看Engine對象的_route()
方法作了什麼。$this->router()
會觸發當前對象的__call()
魔術方法,根據剛纔的分析$this->dispatcher->get($name)
返回null。而$this->loader->get($name)
返回true,而後就去執行$this->loader->load($name, $shared)
。在Load對象的load方法中isset($this->classes[$name])
爲true,isset($this->instances[$name])
返回false,在框架初始化時設置的$params
和$backcall
都爲默認值,因此會執行$this->newInstance($class, $params)
,在newInstance方法中直接return new $class()
。總結:$this->router()
其實就是經過工廠模式去實例化框架初始化時所設置的'\flight\net\Router'
類,依次論推$this->request()、$this->response()、$this->view()
是同樣的邏輯。函數
flight/Engine.phppost
/** * Routes a URL to a callback function. * * @param string $pattern URL pattern to match * @param callback $callback Callback function * @param boolean $pass_route Pass the matching route object to the callback */ public function _route($pattern, $callback, $pass_route = false) { $this->router()->map($pattern, $callback, $pass_route); }
flight/core/Loader.phpui
/** * Loads a registered class. * * @param string $name Method name * @param bool $shared Shared instance * @return object Class instance * @throws \Exception */ public function load($name, $shared = true) { $obj = null; if (isset($this->classes[$name])) { list($class, $params, $callback) = $this->classes[$name]; $exists = isset($this->instances[$name]); if ($shared) { $obj = ($exists) ? $this->getInstance($name) : $this->newInstance($class, $params); if (!$exists) { $this->instances[$name] = $obj; } } else { $obj = $this->newInstance($class, $params); } if ($callback && (!$shared || !$exists)) { $ref = array(&$obj); call_user_func_array($callback, $ref); } } return $obj; } /** * Gets a new instance of a class. * * @param string|callable $class Class name or callback function to instantiate class * @param array $params Class initialization parameters * @return object Class instance * @throws \Exception */ public function newInstance($class, array $params = array()) { if (is_callable($class)) { return call_user_func_array($class, $params); } switch (count($params)) { case 0: return new $class(); case 1: return new $class($params[0]); case 2: return new $class($params[0], $params[1]); case 3: return new $class($params[0], $params[1], $params[2]); case 4: return new $class($params[0], $params[1], $params[2], $params[3]); case 5: return new $class($params[0], $params[1], $params[2], $params[3], $params[4]); default: try { $refClass = new \ReflectionClass($class); return $refClass->newInstanceArgs($params); } catch (\ReflectionException $e) { throw new \Exception("Cannot instantiate {$class}", 0, $e); } } }
那$this->router()->map($pattern, $callback, $pass_route)
操做的目的就是將用戶定義的一個或多個route壓入到Router對象的$routes
屬性索引數組中。至此,index.php中的Flight::route()
操做就結束了,整個操做流程目的就是獲取並解析用戶定義的全部route,存儲到Router對象的$routes
屬性索引數組中。接下來的Flight::start()
,顧名思義,就是拿着處理好的路由請求信息去真正幹活了。
flight/net/Router.php
/** * Maps a URL pattern to a callback function. * * @param string $pattern URL pattern to match * @param callback $callback Callback function * @param boolean $pass_route Pass the matching route object to the callback */ public function map($pattern, $callback, $pass_route = false) { $url = $pattern; $methods = array('*'); //經過用戶route定義的匹配規則,解析定義的methods,如'GET|POST /' if (strpos($pattern, ' ') !== false) { list($method, $url) = explode(' ', trim($pattern), 2); $methods = explode('|', $method); } $this->routes[] = new Route($url, $callback, $methods, $pass_route); }
Flight::start()
要作的工做就是經過Request對象中獲取的真實請求信息與用戶所定義的路由進行匹配驗證,匹配經過的而後經過Response對象返回給用戶請求的結果。
根據剛纔的分析,start()
方法也會去調用Dispatcher類的invokeMethod方法,但$params是null,因此會執行$class->$method()
,經過剛纔的分析,會調用Engine對象__call()
魔術方法的$this->dispatcher->run($name, $params)
。在dispatcher對象的run()方法中,因爲start()方法在框架初始化時設置有前置操做,因此在這裏會執行所設置的前置操做,最後會執行Engine對象的_start()
方法。
這裏重點要分析的是從$route = $router->route($request)
開始的操做。在實例化Request類獲取$request對象時,會作些初始化操做,會將實際的請求信息設置在屬性中,用於和用戶定義的route進行匹配。
/** * Starts the framework. * @throws \Exception */ public function _start() { $dispatched = false; $self = $this; $request = $this->request(); //獲取Request對象 $response = $this->response(); //獲取Response對象 $router = $this->router(); //獲取Router對象 // Allow filters to run 設置start()方法執行的後置操做 $this->after('start', function() use ($self) { $self->stop(); }); // Flush any existing output if (ob_get_length() > 0) { $response->write(ob_get_clean()); } // Enable output buffering ob_start(); // Route the request while ($route = $router->route($request)) { $params = array_values($route->params); // Add route info to the parameter list if ($route->pass) { $params[] = $route; } // Call route handler $continue = $this->dispatcher->execute( $route->callback, $params ); $dispatched = true; if (!$continue) break; $router->next(); $dispatched = false; } if (!$dispatched) { $this->notFound(); } }
flight/net/Request.php
/** * Constructor. * * @param array $config Request configuration */ public function __construct($config = array()) { // Default properties if (empty($config)) { $config = array( 'url' => str_replace('@', '%40', self::getVar('REQUEST_URI', '/')), 'base' => str_replace(array('\\',' '), array('/','%20'), dirname(self::getVar('SCRIPT_NAME'))), 'method' => self::getMethod(), 'referrer' => self::getVar('HTTP_REFERER'), 'ip' => self::getVar('REMOTE_ADDR'), 'ajax' => self::getVar('HTTP_X_REQUESTED_WITH') == 'XMLHttpRequest', 'scheme' => self::getVar('SERVER_PROTOCOL', 'HTTP/1.1'), 'user_agent' => self::getVar('HTTP_USER_AGENT'), 'type' => self::getVar('CONTENT_TYPE'), 'length' => self::getVar('CONTENT_LENGTH', 0), 'query' => new Collection($_GET), 'data' => new Collection($_POST), 'cookies' => new Collection($_COOKIE), 'files' => new Collection($_FILES), 'secure' => self::getVar('HTTPS', 'off') != 'off', 'accept' => self::getVar('HTTP_ACCEPT'), 'proxy_ip' => self::getProxyIpAddress() ); } $this->init($config); }
如今來看$router->route($request)
操做都作了什麼。$route = $this->current()
能夠獲取到剛纔$this->router->map()
保存的用戶定義的第一個route,若是爲false,就會直接返回404。不然,經過$route->matchMethod($request->method) && $route->matchUrl($request->url, $this->case_sensitive)
來匹配驗證用戶定義的routes和實際請求的信息(請求方法和請求url)。
flight/net/Router.php
/** * Routes the current request. * * @param Request $request Request object * @return Route|bool Matching route or false if no match */ public function route(Request $request) { while ($route = $this->current()) { if ($route !== false && $route->matchMethod($request->method) && $route->matchUrl($request->url, $this->case_sensitive)) { return $route; } $this->next(); } return false; }
flight/net/Route.php
/** * Checks if a URL matches the route pattern. Also parses named parameters in the URL. * * @param string $url Requested URL * @param boolean $case_sensitive Case sensitive matching * @return boolean Match status */ public function matchUrl($url, $case_sensitive = false) { // Wildcard or exact match if ($this->pattern === '*' || $this->pattern === $url) { return true; } $ids = array(); $last_char = substr($this->pattern, -1); // Get splat if ($last_char === '*') { $n = 0; $len = strlen($url); $count = substr_count($this->pattern, '/'); for ($i = 0; $i < $len; $i++) { if ($url[$i] == '/') $n++; if ($n == $count) break; } $this->splat = (string)substr($url, $i+1); // /blog/* *匹配的部分 } // Build the regex for matching $regex = str_replace(array(')','/*'), array(')?','(/?|/.*?)'), $this->pattern); //對路由匹配實現正則匹配 "/@name/@id:[0-9]{3}" $regex = preg_replace_callback( '#@([\w]+)(:([^/\(\)]*))?#', function($matches) use (&$ids) { $ids[$matches[1]] = null; if (isset($matches[3])) { return '(?P<'.$matches[1].'>'.$matches[3].')'; } return '(?P<'.$matches[1].'>[^/\?]+)'; }, $regex ); // Fix trailing slash if ($last_char === '/') { $regex .= '?'; } // Allow trailing slash else { $regex .= '/?'; } // Attempt to match route and named parameters if (preg_match('#^'.$regex.'(?:\?.*)?$#'.(($case_sensitive) ? '' : 'i'), $url, $matches)) { foreach ($ids as $k => $v) { $this->params[$k] = (array_key_exists($k, $matches)) ? urldecode($matches[$k]) : null; } $this->regex = $regex; return true; } return false; } /** * Checks if an HTTP method matches the route methods. * * @param string $method HTTP method * @return bool Match status */ public function matchMethod($method) { return count(array_intersect(array($method, '*'), $this->methods)) > 0; }