本篇文章給大家?guī)淼膬?nèi)容是關(guān)于laravel框架下路由的使用（源碼解析），有一定的參考價值，有需要的朋友可以參考一下，希望對你有所幫助。
前言
我的解析文章并非深層次多領(lǐng)域的解析攻略。但是參考著開發(fā)文檔看此類文章會讓你在日常開發(fā)中更上一層樓。
廢話不多說，我們開始本章的講解。
入口
laravel啟動后，會先加載服務(wù)提供者、中間件等組件，在查找路由之前因為我們使用的是門面，所以先要查到Route的實體類。
注冊
第一步當(dāng)然還是通過服務(wù)提供者，因為這是laravel啟動的關(guān)鍵，在 RouteServiceProvider 內(nèi)加載路由文件。
protected function mapApiRoutes() { Route::prefix('api') ->middleware('api') ->namespace($this->namespace) // 設(shè)置所處命名空間 ->group(base_path('routes/api.php')); //所得路由文件絕對路徑 }
首先require是不可缺少的。因路由文件中沒有命名空間。 IlluminateRoutingRouter 下方法
protected function loadRoutes($routes) { if ($routes instanceof Closure) { $routes($this); } else { $router = $this; require $routes; } }
隨后通過路由找到指定方法,依舊是 ?IlluminateRoutingRouter 內(nèi)有你所使用的所有路由相關(guān)方法，例如get、post、put、patch等等，他們都調(diào)用了統(tǒng)一的方法 addRoute
public function addRoute($methods, $uri, $action) { return $this->routes->add($this->createRoute($methods, $uri, $action)); }
之后通過 IlluminateRoutingRouteCollection addToCollections 方法添加到集合中
protected function addToCollections($route) { $domainAndUri = $route->getDomain().$route->uri(); foreach ($route->methods() as $method) { $this->routes[$method][$domainAndUri] = $route; } $this->allRoutes[$method.$domainAndUri] = $route; }
添加后的結(jié)果如下圖所示
調(diào)用
通過 IlluminateRoutingRouter 方法開始運行路由實例化的邏輯
protected function runRoute(Request $request, Route $route) { $request->setRouteResolver(function () use ($route) { return $route; }); $this->events->dispatch(new EventsRouteMatched($route, $request)); return $this->prepareResponse($request, $this->runRouteWithinStack($route, $request) ); } .... protected function runRouteWithinStack(Route $route, Request $request) { $shouldSkipMiddleware = $this->container->bound('middleware.disable') && $this->container->make('middleware.disable') === true; $middleware = $shouldSkipMiddleware ? [] : $this->gatherRouteMiddleware($route); return (new Pipeline($this->container)) ->send($request) ->through($middleware) ->then(function ($request) use ($route) { return $this->prepareResponse( $request, $route->run() // 此處調(diào)用run方法 ); }); }
在 IlluminateRoutingRoute 下 run 方用于執(zhí)行控制器的方法
public function run() { $this->container = $this->container ?: new Container; try { if ($this->isControllerAction()) { return $this->runController(); //運行一個路由并作出響應(yīng) } return $this->runCallable(); } catch (HttpResponseException $e) { return $e->getResponse(); } }
從上述方法內(nèi)可以看出 runController 是運行路由的關(guān)鍵,方法內(nèi)運行了一個調(diào)度程序，將控制器 $this->getController() 和控制器方法 $this->getControllerMethod() 傳入到 dispatch 調(diào)度方法內(nèi)
protected function runController() { return $this->controllerDispatcher()->dispatch( $this, $this->getController(), $this->getControllerMethod() ); }
這里注意 getController() 才是真正的將控制器實例化的方法
public function getController() { if (! $this->controller) { $class = $this->parseControllerCallback()[0]; // 0=>控制器 xxController 1=>方法名 index $this->controller = $this->container->make(ltrim($class, '')); // 交給容器進(jìn)行反射 } return $this->controller; }
實例化
依舊通過反射加載路由指定的控制器,這個時候build的參數(shù)$concrete = ? ?AppApiControllersXxxController
public function build($concrete) { // If the concrete type is actually a Closure, we will just execute it and // hand back the results of the functions, which allows functions to be // used as resolvers for more fine-tuned resolution of these objects. if ($concrete instanceof Closure) { return $concrete($this, $this->getLastParameterOverride()); } $reflector = new ReflectionClass($concrete); // If the type is not instantiable, the developer is attempting to resolve // an abstract type such as an Interface of Abstract Class and there is // no binding registered for the abstractions so we need to bail out. if (! $reflector->isInstantiable()) { return $this->notInstantiable($concrete); } $this->buildStack[] = $concrete; $constructor = $reflector->getConstructor(); // If there are no constructors, that means there are no dependencies then // we can just resolve the instances of the objects right away, without // resolving any other types or dependencies out of these containers. if (is_null($constructor)) { array_pop($this->buildStack); return new $concrete; } $dependencies = $constructor->getParameters(); // Once we have all the constructor's parameters we can create each of the // dependency instances and then use the reflection instances to make a // new instance of this class, injecting the created dependencies in. $instances = $this->resolveDependencies( $dependencies ); array_pop($this->buildStack); return $reflector->newInstanceArgs($instances); }
這時將返回控制器的實例，下面將通過url訪問指定方法，一般控制器都會繼承父類 IlluminateRoutingController ,laravel為其設(shè)置了別名 BaseController
public function dispatch(Route $route, $controller, $method) { $parameters = $this->resolveClassMethodDependencies( $route->parametersWithoutNulls(), $controller, $method ); if (method_exists($controller, 'callAction')) { return $controller->callAction($method, $parameters); } return $controller->{$method}(...array_values($parameters)); }
Laravel通過controller繼承的callAction去調(diào)用子類的指定方法，也就是我們希望調(diào)用的自定義方法。
public function callAction($method, $parameters) { return call_user_func_array([$this, $method], $parameters); }
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