/**
  * Import students account data with excel
  *
  * @param  \Illuminate\Http\Request  $request
  * @return \Illuminate\Http\Response
  */
 public function import(Request $request)
 {
     // get tmp xlsx file path
     $file_path = $request->file('studentData')->getRealPath();
     // extract student data from the file uploaded
     $student_data = Excel::load($file_path)->toArray();
     // processing & storing student data
     foreach ($student_data as $data) {
         $user = new User();
         $user->username = $data['學號'];
         $user->password = str_random(96);
         $user->nickname = $data['姓名'];
         $user->email = $data['信箱'];
         $user->phone = $data['電話'];
         $user->group = $data['班級'];
         $user->save();
         $user->roles()->save(Role::where('name', 'student')->first());
     }
     return response()->json(['status' => 0]);
 }