如何使用Laravel在Maatwebsite Excel Upload中验证唯一多个列

如何解决如何使用Laravel在Maatwebsite Excel Upload中验证唯一多个列

我在Laravel-5.8中有一个项目，可以使用Maatwebsite执行excel上传。

型号

class HrLeaveRequest extends Model
{
  protected $table = 'hr_leave_requests';

  protected $fillable = [
              'id','employee_id','leave_type_id','commencement_date',];
  public function employee()
  {
    return $this->belongsTo('App\Models\Hr\HrEmployee','employee_id');
  } 
  public function leavetype()
  {
    return $this->belongsTo('App\Models\Hr\HrLeaveType','leave_type_id');
  }
}

Excel上传

    $this->staffid = $row['staff_id'];
    $this->leavetype = $row['leave_type'];

    return new HrLeaveRequest([
        'employee_id'                       => $this->getStaffId(),'leave_type_id'                     => $this->getLeaveType(),'commencement_date'                 => $this->transformDate($row['commencement_date']),]); 

  public function getStaffId(){
    return HrEmployee::where('employee_code',$this->staffid)->pluck('id')->first();
  }

  public function getLeaveType(){
    return HrLeaveType::where('leave_type_name',$this->leavetype)->pluck('id')->first();
  }

 public function transformDate($value,$format = 'Y-m-d')
 {
    try {
        return \Carbon\Carbon::instance(\PHPOffice\PHPSpreadsheet\Shared\Date::excelToDateTimeObject($value));
    } catch (\ErrorException $e) {
        return \Carbon\Carbon::createFromFormat($format,$value);
    }
 } 

public function rules(): array
{
    return [
        'staff_id' => 'required|max:15','leave_type' => 'required|max:255','commencement_date' => 'required',];
}  

我想验证staff_id，leave_type和beginment_date为“唯一多个”列。也就是说，它们中的三（3）个是唯一的。

我该如何实现？

谢谢