请求 cloudinary 资源会出现 CORS 错误

Question

我有一个 laravel/lumen 服务器管理我的云端资源的上传。我还将服务器用作我的前端应用程序的 API 端点。端点之一 returns 来自 Cloudinary 的文件。我通过将请求重定向到 Cloudinary 资源来执行此操作。但是我的应用程序失败了，因为重定向的资源上没有 CORS headers。

return redirect()->to("https://res.cloudinary.com/gates/raw/upload/" . $upload->id);

我得到的错误是：

Redirect from 'https://{my-server.com}/api/v1/export' to 
'https://res.cloudinary.com/gates/raw/upload/{upload-id}' has been 
blocked by CORS policy: No 'Access-Control-Allow-Origin' header is 
present on the requested resource. Origin 'https://{my-frontend.com}' 
is therefore not allowed access.

Answer 1

您可以在您的服务器上使用这个库：https://github.com/barryvdh/laravel-cors

return [
     /*
     |--------------------------------------------------------------------------
     | Laravel CORS
     |--------------------------------------------------------------------------
     |
     | allowedOrigins, allowedHeaders and allowedMethods can be set to array('*')
     | to accept any value.
     |
     */
    'supportsCredentials' => false,
    'allowedOrigins' => ['*'],
    'allowedHeaders' => ['Content-Type', 'X-Requested-With'],
    'allowedMethods' => ['*'], // ex: ['GET', 'POST', 'PUT',  'DELETE']
    'exposedHeaders' => [],
    'maxAge' => 0,
]


allowedOrigins => [*] mean that you give access to your server, you can add ip's or dns for restrict access to your server

Answer 2

Here is my CORS middleware:

use Closure;

class CORS {

    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     */
    public function handle($request, Closure $next)
    {

        header("Access-Control-Allow-Origin: *");

        // ALLOW OPTIONS METHOD
        $headers = [
            'Access-Control-Allow-Methods'=> 'POST, GET, OPTIONS, PUT, DELETE',
            'Access-Control-Allow-Headers'=> 'Content-Type, X-Auth-Token, Origin'
        ];
        if($request->getMethod() == "OPTIONS") {
            // The client-side application can set only headers allowed in Access-Control-Allow-Headers
            return Response::make('OK', 200, $headers);
        }

        $response = $next($request);
        foreach($headers as $key => $value)
            $response->header($key, $value);
        return $response;
    }

}

To use CORS middleware you have to register it first in your app\Http\Kernel.php file like this:

protected $routeMiddleware = [
        //other middlewares
        'cors' => 'App\Http\Middleware\CORS',
    ];

Then you can use it in your routes

Route::get('example', array('middleware' => 'cors', 'uses' => 'ExampleController@dummy'));

请求 cloudinary 资源会出现 CORS 错误

requesting cloudinary resource gives CORS errors

php

cors

laravel

cloudinary