laravel ajax验证

 public function login(Request $request){
        if($request->isMethod('post')){
            $data = json_decode($request->input("data"),true);
            $validator =\Illuminate\Support\Facades\Validator::make($data,
                [
                    'username'=>'required|max:100',
                    'password'=>'required'
                ],
                [
                    'username.required' => 'username字段不能为空',
                    'password.required' => 'password字段不能为空',
                    'username.max' => 'username长度必须小于100',
                ]
            );

            if ($validator->fails()) {
                return response()->json(['code' => "201", "msg" => $validator->errors()->first()]);
            }
            $res =Administrator::where(['username'=>$data['username'],'pwd'=>md5($data['password'])])->first();
            if($res){
                $request->session()->put("admin",$res['id']);
                return response()->json(['code'=>200,'msg'=>'登录成功',]);
            }else{
                return response()->json(['code'=>500,'msg'=>'登录失败']);
            }
        }else{
            return view('login');
        }
    }