Laravel中間件

php artisan make:middleware <middleware-name> 

使用你的中間件名稱替換<middleware-name>。創(chuàng)建可以看到中間件在 app/Http/Middleware 目錄。

示例

php artisan make:middleware AgeMiddleware

第2步 - 命令成功執(zhí)行后，會(huì)收到以下輸出 -

第3步 ? AgeMiddlware 會(huì)在 app/Http/Middleware 文件中創(chuàng)建。新創(chuàng)建的文件將自動(dòng)創(chuàng)建下面代碼：

<?php
namespace App\Http\Middleware;
use Closure;

class AgeMiddleware {
   public function handle($request, Closure $next) {
      return $next($request);
   }
}

注冊(cè)中間件

• 全局中間件
• 路由中間件

全局中間件將在應(yīng)用程序的每個(gè)HTTP請(qǐng)求運(yùn)行，而路由中間件將被分配到一個(gè)特定的路由。中間件可在 app/Http/Kernel.php 注冊(cè). 
該文件包含兩個(gè)屬性： $middleware 和 $routeMiddleware。$middleware 屬性用于注冊(cè)全局中間件，$routeMiddleware屬性用于注冊(cè)路由指定中間件。

protected $middleware = [
   \Illuminate\Foundation\Http\Middleware\CheckForMaintenanceMode::class,
   \App\Http\Middleware\EncryptCookies::class,
   \Illuminate\Cookie\Middleware\AddQueuedCookiesToResponse::class,
   \Illuminate\Session\Middleware\StartSession::class,
   \Illuminate\View\Middleware\ShareErrorsFromSession::class,
   \App\Http\Middleware\VerifyCsrfToken::class,
];

protected $routeMiddleware = [
   'auth' => \App\Http\Middleware\Authenticate::class,
   'auth.basic' => \Illuminate\Auth\Middleware\AuthenticateWithBasicAuth::class,
   'guest' => \App\Http\Middleware\RedirectIfAuthenticated::class,
];

示例

我們已經(jīng)在前面的例子中已創(chuàng)建 AgeMiddleware 中間件。 現(xiàn)在，我們可以在具體的路由中間件屬性登記。注冊(cè)代碼如下所示。

<?php
namespace App\Http;
use Illuminate\Foundation\Http\Kernel as HttpKernel;

class Kernel extends HttpKernel {
   protected $middleware = [
      \Illuminate\Foundation\Http\Middleware\CheckForMaintenanceMode::class,
      \App\Http\Middleware\EncryptCookies::class,
      \Illuminate\Cookie\Middleware\AddQueuedCookiesToResponse::class,
      \Illuminate\Session\Middleware\StartSession::class,
      \Illuminate\View\Middleware\ShareErrorsFromSession::class,
      \App\Http\Middleware\VerifyCsrfToken::class,
   ];
  
   protected $routeMiddleware = [
      'auth' => \App\Http\Middleware\Authenticate::class,
      'auth.basic' => \Illuminate\Auth\Middleware\AuthenticateWithBasicAuth::class,
      'guest' => \App\Http\Middleware\RedirectIfAuthenticated::class,
      'Age' => \App\Http\Middlware\AgeMiddleware::class,
   ];
}

中間件參數(shù)

我們也可以傳遞中間件參數(shù)。例如，如果您的應(yīng)用程序有不同角色，如用戶，管理員，超級(jí)管理員等，并且要驗(yàn)證基于角色的動(dòng)作，這可以通過參數(shù)傳遞中間件來實(shí)現(xiàn)。我們創(chuàng)建的中間件包含以下功能，我們可以通過 $next 參數(shù)之后，自定義參數(shù)。

public function handle($request, Closure $next) {
   return $next($request);
}

示例

php artisan make:middleware RoleMiddleware

第2步 - 成功執(zhí)行后，會(huì)收到以下輸出

第3步  ? 添加以下代碼到新創(chuàng)建的角色中間件的處理方法 - app/Http/Middleware/RoleMiddleware.php.

<?php
namespace App\Http\Middleware;
use Closure;

class RoleMiddleware {
   public function handle($request, Closure $next, $role) {
      echo "Role: ".$role;
      return $next($request);
   }
}

第4步  ? 在 app\Http\Kernel.php 文件中注冊(cè)角色中間件。 加入灰色突出的線條的是在該文件中注冊(cè) RoleMiddleware 中間件。

php artisan make:controller TestController

第6步 - 成功執(zhí)行后，您會(huì)收到以下輸出 -

app/Http/TestController.php

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use App\Http\Requests;
use App\Http\Controllers\Controller;

class TestController extends Controller {
   public function index(){
      echo "<br>Test Controller.";
   }
}

app/Http/routes.php

Route::get('role',[
   'middleware' => 'Role:editor',
   'uses' => 'TestController@index',
]);

http://localhost:8000/role

第10步 - 輸出顯示如下圖中所示。

可終止的中間件

響應(yīng)已經(jīng)發(fā)送給瀏覽器后可終止中間件執(zhí)行一些任務(wù)。這可以通過使用創(chuàng)建中間件“終止”方法的中間件來實(shí)現(xiàn)?？山K止中間件會(huì)注冊(cè)全局中間件。該終止方法將接受兩個(gè)參數(shù)：$request 和 $response。終止方法可以被創(chuàng)建，如在下面顯示的代碼。

示例

php artisan make:middleware TerminateMiddleware

第2步 - 這將產(chǎn)生以下輸出 -

第3步 - 復(fù)制下面的代碼到新創(chuàng)建文件 - TerminateMiddleware 在 app/Http/Middleware/TerminateMiddleware.php 文件中如下：

<?php
namespace App\Http\Middleware;
use Closure;

class TerminateMiddleware {
   public function handle($request, Closure $next) {
      echo "Executing statements of handle method of TerminateMiddleware.";
      return $next($request);
   }
   
   public function terminate($request, $response){
      echo "<br>Executing statements of terminate method of TerminateMiddleware.";
   }
}

第4步  ? 注冊(cè) TerminateMiddleware 到 app\Http\Kernel.php 文件中.

加了灰色突出的線條的是該文件中注冊(cè)的 TerminateMiddleware 中間件。

php artisan make:controller ABCController

第6步 - URL成功執(zhí)行后，會(huì)收到以下輸出 -

app/Http/ABCController.php

<?php
namespace App\Http\Controllers;
use Illuminate\Http\Request;
use App\Http\Requests;
use App\Http\Controllers\Controller;

class ABCController extends Controller {
   public function index(){
      echo "<br>ABC Controller.";
   }
}

app/Http/routes.php

Route::get('terminate',[
   'middleware' => 'terminate',
   'uses' => 'ABCController@index',
]);

http://localhost:8000/terminate

第10步 - 如下面的圖片輸出的結(jié)果。