config/app.php
'providers' =>[
Laravel\Passport\PassportServiceProvider::class,
],

php artisan migrate
php artisan passport:install

<?php
namespace App;
use Laravel\Passport\HasApiTokens;
use Illuminate\Notifications\Notifiable;
use Illuminate\Foundation\Auth\User as Authenticatable;
class User extends Authenticatable
{
  use HasApiTokens, Notifiable;
/**
* The attributes that are mass assignable.
*
* @var array
*/
protected $fillable = [
'name', 'email', 'password',
];
/**
* The attributes that should be hidden for arrays.
*
* @var array
*/
protected $hidden = [
'password', 'remember_token',
];
}

<?php
namespace App\Providers;
use Laravel\Passport\Passport; 
use Illuminate\Support\Facades\Gate; 
use Illuminate\Foundation\Support\Providers\AuthServiceProvider as ServiceProvider;
class AuthServiceProvider extends ServiceProvider 
{ 
    /** 
     * The policy mappings for the application. 
     * 
     * @var array 
     */ 
    protected $policies = [ 
        'App\Model' => 'App\Policies\ModelPolicy', 
    ];
/** 
     * Register any authentication / authorization services. 
     * 
     * @return void 
     */ 
    public function boot() 
    { 
        $this->registerPolicies(); 
        Passport::routes(); 
    } 
}

<?php
return [
'guards' => [ 
        'web' => [ 
            'driver' => 'session', 
            'provider' => 'users', 
        ], 
        'api' => [ 
            'driver' => 'passport', 
            'provider' => 'users', 
        ], 
    ],

<?php
/*
|--------------------------------------------------------------------------
| API Routes
|--------------------------------------------------------------------------
|
| Here is where you can register API routes for your application. These
| routes are loaded by the RouteServiceProvider within a group which
| is assigned the "api" middleware group. Enjoy building your API!
|
*/
Route::post('login', 'API\UserController@login');
Route::post('register', 'API\UserController@register');
Route::group(['middleware' => 'auth:api'], function(){
Route::post('details', 'API\UserController@details');
});

<?php
namespace App\Http\Controllers\API;
use Illuminate\Http\Request; 
use App\Http\Controllers\Controller; 
use App\User; 
use Illuminate\Support\Facades\Auth; 
use Validator;
class UserController extends Controller 
{
public $successStatus = 200;
/** 
     * login api 
     * 
     * @return \Illuminate\Http\Response 
     */ 
    public function login(){ 
        if(Auth::attempt(['email' => request('email'), 'password' => request('password')])){ 
            $user = Auth::user(); 
            $success['token'] =  $user->createToken('MyApp')-> accessToken; 
            return response()->json(['success' => $success], $this-> successStatus); 
        } 
        else{ 
            return response()->json(['error'=>'Unauthorised'], 401); 
        } 
    }
/** 
     * Register api 
     * 
     * @return \Illuminate\Http\Response 
     */ 
    public function register(Request $request) 
    { 
        $validator = Validator::make($request->all(), [ 
            'name' => 'required', 
            'email' => 'required|email', 
            'password' => 'required', 
            'c_password' => 'required|same:password', 
        ]);
if ($validator->fails()) { 
            return response()->json(['error'=>$validator->errors()], 401);            
        }
$input = $request->all(); 
        $input['password'] = bcrypt($input['password']); 
        $user = User::create($input); 
        $success['token'] =  $user->createToken('MyApp')-> accessToken; 
        $success['name'] =  $user->name;
return response()->json(['success'=>$success], $this-> successStatus); 
    }
/** 
     * details api 
     * 
     * @return \Illuminate\Http\Response 
     */ 
    public function details() 
    { 
        $user = Auth::user(); 
        return response()->json(['success' => $user], $this-> successStatus); 
    } 
}

php artisan serve