Method Illuminate\Auth\RequestGuard::attempt does not exist

Question

I am new to both laravel and lumen. I was creating a login api with oauth2.0 in lumen 5.6, i have installed passport and generated token. Below is my login controller function a

Answer 1

Changing default guard to "web" fixed my problem.

config/auth.php:

'defaults' => [
        'guard' => 'web',
        'passwords' => 'users',
    ],

Answer 2

The function guard is only available for routes with web middleware

public function login() {

  if(Auth::guard('web')->attempt(['email' => $email, 'password' => $password], false, false)) {requests
     // good
  } else {
    // invalid credentials, act accordingly
 }
}