Laravel 中的 Auth

laravel 中有一个组件叫 auth，auth 组件提供了整个框架的认证功能，这里想简单追踪一下它的实现逻辑。

首先从 php artisan make:auth 开始

# Illuminate\Auth\Console\AuthMakeCommand.php

public function handle()
{
    // 创建存放 auth 前端界面的目录和文件
    // 模版存放在 Auth\Console 的 stubs 下
    $this->createDirectories();
    $this->exportViews();

    if (! $this->option('views')) {
        // 生成 HomeController 控制器文件
        file_put_contents(app_path('Http/Controllers/HomeController.php'),
            $this->compileControllerStub());
        // 生成 auth 相关路由
    file_put_contents(base_path('routes/web.php'),
        file_get_contents(__DIR__.'/stubs/make/routes.stub'),
        FILE_APPEND
        );
    }
}

生成文件 resources/views/auth、resources/layouts 路由文件 web.php、和 Http/Controllers/Auth 下的控制器

说一说 csrf-token

<!-- CSRF Token -->
<meta name="csrf-token" content="{{csrf_token() }}">

        function csrf_token()
    {$session = app('session');

        if (isset($session)) {return $session->token();
        }

        throw new RuntimeException('Application session store not set.');
    }

LoginController 的 login 方法

    public function login(Request $request)
    {
                // 检查请求体
        $this->validateLogin($request);
                // 判断是否请求失败太多次
        if ($this->hasTooManyLoginAttempts($request)) {$this->fireLockoutEvent($request);

            return $this->sendLockoutResponse($request);
        }
                // 判断是否验证通过
        if ($this->attemptLogin($request)) {return $this->sendLoginResponse($request);
        }
                // 记录请求失败次数
        $this->incrementLoginAttempts($request);

        return $this->sendFailedLoginResponse($request);
    }

登录验证方法 attemptLogin

通过 Auth::guard() 引导到 Illuminate\Auth\AuthManager
先看  服务提供者  AuthServiceProvider
AuthServiceProvider 注册四个服务

protected function registerAuthenticator()
    {$this->app->singleton('auth', function ($app) {$app['auth.loaded'] = true;
                        // 生成一个 AuthManager 实例
            return new AuthManager($app);
        });

        $this->app->singleton('auth.driver', function ($app) {return $app['auth']->guard();});
    }

protected function registerUserResolver()
    {
        $this->app->bind(AuthenticatableContract::class, function ($app) {return call_user_func($app['auth']->userResolver());
            }
        );
    }

protected function registerAccessGate()
    {$this->app->singleton(GateContract::class, function ($app) {return new Gate($app, function () use ($app) {return call_user_func($app['auth']->userResolver());
            });
        });
    }

protected function registerRequestRebindHandler()
    {$this->app->rebinding('request', function ($app, $request) {$request->setUserResolver(function ($guard = null) use ($app) {return call_user_func($app['auth']->userResolver(), $guard);
            });
        });
    }

生成一个 AuthManager 实例
AuthManager 中的 trait CreatesUserProviders
这个 trait 是用来绑定一个用户认证的 Eloqument 服务提供者

public function __construct($app)
    {
                // 绑定 application 实例
        $this->app = $app;
                // 绑定一个闭包，用于解析用户。// 通过 $guard 来确定用户解析用户的方法
        $this->userResolver = function ($guard = null) {return $this->guard($guard)->user();};
    }

protected function resolve($name)
    {$config = $this->getConfig($name);

                // 根据配置调用不同的解析用户的驱动方法
        $driverMethod = 'create'.ucfirst($config['driver']).'Driver';

        if (method_exists($this, $driverMethod)) {return $this->{$driverMethod}($name, $config);
        }
    }

分别定位的两个方法

        public function createSessionDriver($name, $config)
    {
                //     根据配置文件创建一个相应的 provider
        $provider = $this->createUserProvider($config['provider'] ?? null);
                
                $guard = new SessionGuard($name, $provider, $this->app['session.store']);

        return $guard;
    }
    
    public function createTokenDriver($name, $config)
    {
        $guard = new TokenGuard($this->createUserProvider($config['provider'] ?? null),
            $this->app['request'],
            $config['input_key'] ?? 'api_token',
            $config['storage_key'] ?? 'api_token'
        );
        return $guard;
    }

于是得到 $this->guard($guard) 的 user()方法
先看如何实例一个 TokenGuard 类

public function __construct(UserProvider $provider, Request $request, $inputKey = 'api_token', $storageKey = 'api_token')
    {
        $this->request = $request;
        $this->provider = $provider;
        $this->inputKey = $inputKey;
        $this->storageKey = $storageKey;
    }

# Illuminate\Auth\TokenGuard

    public function user()
    {if (! is_null($this->user)) {return $this->user;}

        $user = null;
                // 从 request 中获取 token
        $token = $this->getTokenForRequest();

        if (! empty($token)) {
                        // 通过用户 provider 中的 retrieveByCredentials 方法来判断用户是否认证成功
            $user = $this->provider->retrieveByCredentials([$this->storageKey => $token]
            );
        }

        return $this->user = $user;
    }

上面都是通用的加载引导调用功能，下面的用户服务提供者则是可以修改自定义的认证的具体功能

认证绑定的用户数据提供者

# Illuminate\Auth\DatabaseUserProvider

    public function retrieveByCredentials(array $credentials)
    {if (empty($credentials) ||
           (count($credentials) === 1 &&
            array_key_exists('password', $credentials))) {return;}
        $query = $this->conn->table($this->table);

        foreach ($credentials as $key => $value) {if (Str::contains($key, 'password')) {continue;}

            if (is_array($value) || $value instanceof Arrayable) {$query->whereIn($key, $value);
            } else {$query->where($key, $value);
            }
        }
        
        $user = $query->first();
        
        // 返回 auth 用户数据包
        return $this->getGenericUser($user);
    }