这篇文章主要介绍了laravel框架用户登陆身份验证实现方法,结合实例形式分析了laravel框架用户登陆验证的原理、实现方法与相关注意事项,需要的朋友可以参考下
本文实例讲述了Laravel框架用户登陆身份验证实现方法。分享给大家供大家参考，具体如下：
laravel中检测用户是否登录，有以下的代码：
if ( !Auth::guest() )
{
return Redirect::to('/dashboard');
}那Auth::guest是如何调用的呢？
laravel用了Facade模式，相关门面类在laravel/framework/src/Illuminate/Support/Facades文件夹定义的，看下Auth类的定义：
class Auth extends Facade {
/**
* Get the registered name of the component.
*
* @return string
*/
protected static function getFacadeAccessor() { return 'auth'; }
}laravel框架中，Facade模式使用反射，相关方法其实调用app['auth']中的方法，app['auth']是什么时候创建的呢，
AuthServiceProvider::register方法会注册：
$this->app->bindShared('auth', function($app)
{
// Once the authentication service has actually been requested by the developer
// we will set a variable in the application indicating such. This helps us
// know that we need to set any queued cookies in the after event later.
$app['auth.loaded'] = true;
return new AuthManager($app);
});那为什么最终会调到哪里呢，看下堆栈：
Illuminate\Support\Facades\Auth::guest()
Illuminate\Support\Facades\Facade::__callStatic
Illuminate\Auth\AuthManager->guest()
Illuminate\Support\Manager->__call
public function __call($method, $parameters)
{
return call_user_func_array(array($this->driver(), $method), $parameters);
}看下driver的代码：
public function driver($driver = null)
{
$driver = $driver ?: $this->getDefaultDriver();
// If the given driver has not been created before, we will create the instances
// here and cache it so we can return it next time very quickly. If there is
// already a driver created by this name, we'll just return that instance.
if ( ! isset($this->drivers[$driver]))
{
$this->drivers[$driver] = $this->createDriver($driver);
}
return $this->drivers[$driver];
}没有会调用getDefaultDrive方法
/**
* Get the default authentication driver name.
*
* @return string
*/
public function getDefaultDriver()
{
return $this->app['config']['auth.driver'];
}最终调用的是配置文件中配置的driver，如果配的是
'driver' => 'eloquent'
则调用的是
public function createEloquentDriver()
{
$provider = $this->createEloquentProvider();
return new Guard($provider, $this->app['session.store']);
}所以Auth::guest最终调用的是Guard::guest方法
这里的逻辑先从session中取用户信息，奇怪的是session里只保存的是用户ID，然后拿这个ID来从数据库中取用户信息
public function user()
{
if ($this->loggedOut) return;
// If we have already retrieved the user for the current request we can just
// return it back immediately. We do not want to pull the user data every
// request into the method because that would tremendously slow an app.
if ( ! is_null($this->user))
{
return $this->user;
}
$id = $this->session->get($this->getName());
// First we will try to load the user using the identifier in the session if
// one exists. Otherwise we will check for a "remember me" cookie in this
// request, and if one exists, attempt to retrieve the user using that.
$user = null;
if ( ! is_null($id))
{
//provider为EloquentUserProvider
$user = $this->provider->retrieveByID($id);
}
// If the user is null, but we decrypt a "recaller" cookie we can attempt to
// pull the user data on that cookie which serves as a remember cookie on
// the application. Once we have a user we can return it to the caller.
$recaller = $this->getRecaller();
if (is_null($user) && ! is_null($recaller))
{
$user = $this->getUserByRecaller($recaller);
}
return $this->user = $user;
} 
