无效输入数据 Javascript 的 API 响应和错误消息

Question

假设我有一个存储在我的数据库中的数据列表。那么当用户输入了无效的semesterId 或无效的classId 或无效的dayofWeek 时，如何显示错误信息和API 响应以使我的后端不会崩溃？

以下是发出的请求，其中包含无效的 termId 和错误的 dayofWeek

//SEND REQUEST 
GET http://localhost:3000/basic/result?semesterId=2020100001&classId=4110000001&dayofWeek=9 HTTP/1.1
Content-Type: application/json

这是我的 API

app.get('/basic/result', function (req, res, next) {

  const { classId, semesterId, dayofWeek } = req.query;
  //send the function to the backend 
  database.getDayLecture(classId, semesterId, dayofWeek, (error, result) => {
    const sortResult = backend.minHalls(result);
    if (error) {
      return next(error);
    }else {
        return res.json({
          result: sortResult,
        });
      }
  });
});

谁能帮我解决这个问题？谢谢！

Answer 1

如果我没看错，你应该添加额外的查询参数检查。

app.get('/basic/result', function (req, res, next) {

  const queryParamsValidator = (classId, semesterId, dayofWeek) => {
    return true; // TODO: add your validation logic here
  }

  const { classId, semesterId, dayofWeek } = req.query;

  if (!queryParamsValidator(classId, semesterId, dayofWeek)) {
    return next('Params are invalid!'); // TODO: specify your error here
  }

  database.getDayLecture(classId, semesterId, dayofWeek, (error, result) => {
    const sortResult = backend.minHalls(result);

    if (error) {
      return next(error);
    } else {
      return res.json({
         result: sortResult
      });
    }
  });

});