Adding Access-Control-Allow-Origin header response in Laravel 5.3 Passport

Question

I'm new to Laravel and am doing some Laravel 5.3 Passport project with OAuth2.0 password grant. When I curl the API with the params it responds with token. However, in browser it needs an additional security that the endpoint should add because my request is coming from localhost while the API is located in my VM. Here's the error:

No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:8080' is therefore not allowed access. The response had HTTP status code 400.

I know what the issue is but I don't know where to put to include that header since this is a third party app.

Thank you in advance experts. Please help.

Answer 1

The simple answer is to set the Access-Control-Allow-Origin header to localhost or *. Here's how I usually do it:

Create a simple middleware called Cors:

php artisan make:middleware Cors

Add the following code to app/Http/Middleware/Cors.php:

public function handle($request, Closure $next)
{
    return $next($request)
        ->header('Access-Control-Allow-Origin', '*')
        ->header('Access-Control-Allow-Methods', 'GET, POST, PUT, DELETE, OPTIONS');
}

You can replace the * with localhost or keep it as it is.

Next step is to load the middleware. Add the following line to the $routeMiddleware array in app/Http/Kernel.php.

'cors' => \App\Http\Middleware\Cors::class, 

And the final step is to use the middleware on the routes to which you want to set the access origin headers. Assuming you are talking about the new api routes in laravel 5.3, the place to do it is app/Providers/RouteServiceProvider.php, inside the mapApiRoutes() function (you can remove or comment the previous code of the function):

    Route::group([
        'middleware' => ['api', 'cors'],
        'namespace' => $this->namespace,
        'prefix' => 'api',
    ], function ($router) {
         //Add you routes here, for example:
         Route::apiResource('/posts','PostController');
    });

Answer 2

The simple answer is to set the Access-Control-Allow-Origin header to localhost or *. Here's how I usually do it:

Add the following code to bootstrap/app.php:

header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: *');
header('Access-Control-Allow-Headers: *');

Answer 3

You could also use the great laravel-cors package by barryvdh.

After you have the package installed, the easiest way to get CORS support for all your routes is to add the middleware like this in Http/Kernel.php:

protected $middleware = [
    \Illuminate\Foundation\Http\Middleware\CheckForMaintenanceMode::class,
    \Barryvdh\Cors\HandleCors::class,
];

If you dont want to have CORS support on all your routes you should make a new OPTIONS route for /oauth/token and add the cors middleware to that route only.

Answer 4

For those who didn't solve the problem setting route middleware in App\Http\Kernel, try to set global middleware. In App\Http\Middleware\Cors:

public function handle($request, Closure $next)
{
    return $next($request)->header('Access-Control-Allow-Origin', '*')
        ->header('Access-Control-Allow-Methods','GET', 'POST', 'PUT', 'PATCH', 'DELETE', 'OPTIONS')
        ->header('Access-Control-Allow-Headers', 'Content-Type, Authorization');
}

In App\Http\Kernel:

protected $middleware = [
    ...
    \App\Http\Middleware\Cors::class,
];

Answer 5

Be careful, you can not modify the preflight. In addition, the browser (at least chrome) removes the "authorization" header ... this results in some problems that may arise according to the route design. For example, a preflight will never enter the passport route sheet since it does not have the header with the token.

In case you are designing a file with an implementation of the options method, you must define in the route file web.php one (or more than one) "trap" route so that the preflght (without header authorization) can resolve the request and Obtain the corresponding CORS headers. Because they can not return in a middleware 200 by default, they must add the headers on the original request.

Answer 6

Just add this to your view:

<?php header("Access-Control-Allow-Origin: *"); ?>

Answer 7

Create A Cors.php File in App/Http/Middleware and paste this in it. ☑

<?php

namespace App\Http\Middleware;

use Closure;


class Cors {    public function handle($request, Closure $next)
    {
        header("Access-Control-Allow-Origin: *");
        //ALLOW OPTIONS METHOD
        $headers = [
            'Access-Control-Allow-Methods' => 'POST,GET,OPTIONS,PUT,DELETE',
            'Access-Control-Allow-Headers' => 'Content-Type, X-Auth-Token, Origin, Authorization',
        ];
        if ($request->getMethod() == "OPTIONS"){
            //The client-side application can set only headers allowed in Access-Control-Allow-Headers
            return response()->json('OK',200,$headers);
        }
        $response = $next($request);
        foreach ($headers as $key => $value) {
            $response->header($key, $value);
        }
        return $response;

    } }

And Add This Line In Your Kernel.php after the "Trust Proxies::Class" Line.

\App\Http\Middleware\Cors::class,

Thats It You have Allowed All Cors Header. ☑

Answer 8

Just add this to your code Controller

return response()->json(compact('token'))->header("Access-Control-Allow-Origin",  "*");