中間件有：1、Authenticate；2、CheckForMaintenanceMode；3、EncryptCookies；4、RedirectIfAuthenticated；5、TrimStrings；6、TrustProxies等等。

本教程操作環(huán)境：windows7系統(tǒng)、Laravel6版、Dell G3電腦。

Laravel自帶的中間件

Laravel 自帶了一些中間件，包括身份驗(yàn)證、CSRF 保護(hù)等。Laravel 具體啟用了哪些中間件，可通過(guò) appHttpKernel.php 文件查看。對(duì)于以 AppHttpMiddleware 開(kāi)頭的中間件（位于 app/Http/Middleware 目錄）是我們可以對(duì)其行為進(jìn)行定制的中間件。

Authenticate 中間件

源文件：appHttpMiddlewareHttpMiddlewareAuthenticate.php

<?php namespace AppHttpMiddleware; use IlluminateAuthMiddlewareAuthenticate as Middleware; class Authenticate extends Middleware {     /**      * Get the path the user should be redirected to when they are not authenticated.      *      * @param  IlluminateHttpRequest  $request      * @return string      */     protected function redirectTo($request)     {         if (! $request->expectsJson()) {             return route('login');         }     } }

作用：

用戶身份驗(yàn)證。可修改 redirectTo 方法，返回未經(jīng)身份驗(yàn)證的用戶應(yīng)該重定向到的路徑。

CheckForMaintenanceMode 中間件

源文件 ：appHttpMiddlewareCheckForMaintenanceMode.php

<?php namespace AppHttpMiddleware; use IlluminateFoundationHttpMiddlewareCheckForMaintenanceMode as Middleware; class CheckForMaintenanceMode extends Middleware {     /**      * The URIs that should be reachable while maintenance mode is enabled.      *      * @var array      */     protected $except = [         //     ]; }

作用：

檢測(cè)項(xiàng)目是否處于 維護(hù)模式?？赏ㄟ^(guò) $except 數(shù)組屬性設(shè)置在維護(hù)模式下仍能訪問(wèn)的網(wǎng)址。

EncryptCookies 中間件

源文件：appHttpMiddlewareEncryptCookies.php

<?php namespace AppHttpMiddleware; use IlluminateCookieMiddlewareEncryptCookies as Middleware; class EncryptCookies extends Middleware {     /**      * The names of the cookies that should not be encrypted.      *      * @var array      */     protected $except = [         //     ]; }

作用

對(duì) Cookie 進(jìn)行加解密處理與驗(yàn)證?？赏ㄟ^(guò) $except 數(shù)組屬性設(shè)置不做加密處理的 cookie。

RedirectIfAuthenticated 中間件

源文件：appHttpMiddlewareRedirectIfAuthenticated.php

<?php namespace AppHttpMiddleware; use Closure; use IlluminateSupportFacadesAuth; class RedirectIfAuthenticated {     /**      * Handle an incoming request.      *      * @param  IlluminateHttpRequest  $request      * @param  Closure  $next      * @param  string|null  $guard      * @return mixed      */     public function handle($request, Closure $next, $guard = null)     {         if (Auth::guard($guard)->check()) {             return redirect('/home');         }         return $next($request);     } }

作用：

當(dāng)請(qǐng)求頁(yè)是 注冊(cè)、登錄、忘記密碼 時(shí)，檢測(cè)用戶是否已經(jīng)登錄，如果已經(jīng)登錄，那么就重定向到首頁(yè)，如果沒(méi)有就打開(kāi)相應(yīng)界面?？梢栽?handle 方法中定制重定向到的路徑。

TrimStrings 中間件

源文件：appHttpMiddlewareTrimStrings.php

<?php namespace AppHttpMiddleware; use IlluminateFoundationHttpMiddlewareTrimStrings as Middleware; class TrimStrings extends Middleware {     /**      * The names of the attributes that should not be trimmed.      *      * @var array      */     protected $except = [         'password',         'password_confirmation',     ]; }

作用：

對(duì)請(qǐng)求參數(shù)內(nèi)容進(jìn)行 前后空白字符清理?？赏ㄟ^(guò) $except 數(shù)組屬性設(shè)置不做處理的參數(shù)。

TrustProxies 中間件

源文件：appHttpMiddlewareTrustProxies.php

<?php namespace AppHttpMiddleware; use IlluminateHttpRequest; use FideloperProxyTrustProxies as Middleware; class TrustProxies extends Middleware {     /**      * The trusted proxies for this application.      *      * @var array|string      */     protected $proxies;     /**      * The headers that should be used to detect proxies.      *      * @var int      */     protected $headers = Request::HEADER_X_FORWARDED_ALL; }

作用：

配置可信代理?？赏ㄟ^(guò) $proxies 屬性設(shè)置可信代理列表，$headers 屬性設(shè)置用來(lái)檢測(cè)代理的 HTTP 頭字段。

VerifyCsrfToken 中間件

源文件：appHttpMiddlewareVerifyCsrfToken.php

<?php namespace AppHttpMiddleware; use IlluminateFoundationHttpMiddlewareVerifyCsrfToken as Middleware; class VerifyCsrfToken extends Middleware {     /**      * Indicates whether the XSRF-TOKEN cookie should be set on the response.      *      * @var bool      */     protected $addHttpCookie = true;     /**      * The URIs that should be excluded from CSRF verification.      *      * @var array      */     protected $except = [         //     ]; }

作用：

驗(yàn)證請(qǐng)求里的令牌是否與存儲(chǔ)在會(huì)話中令牌匹配?？赏ㄟ^(guò) $except 數(shù)組屬性設(shè)置不做 CSRF 驗(yàn)證的網(wǎng)址。