RetrieveByUserIdentifier as a callback method (express)

Question

RetrieveByUserIdentifier as a callback method (express)

Can you help me refactor the code below to use a callback function instead? I want to ensure that the Req and Res logic is handled separately.

Userservice.js

function getByUserId(req, res, next) {

  let userIDD = req.body.userID;
  User.findOne({
    userID: userIDD
  }, function(err, result) {
    if (err) {
      console.log("error: " + err)
    } else {

      console.log("Great!");
      res.send(result)
    }
  })
}

UserRoute.js

router.post('/publicUser/getByUserID', userService.getByUserId)

javascript express callback crud

Answer 1

Answer №1

By my reckoning, the current state is satisfactory. However, if you wish to implement a callback and utilize this function as a middleware, you have the option of using next(result) instead of res.send(result).

Answer 2

By my reckoning, the current state is satisfactory. However, if you wish to implement a callback and utilize this function as a middleware, you have the option of using next(result) instead of res.send(result).

Answer 3

Answer №2

To define a callback function directly within your post method, you can utilize an arrow function like so:

router.post('/publicUser/getByUserID', (req, res) => {
  let userID = req.body.userID;
  User.findOne({
    userID: userID
  }, function(err, result) {
    if (err) {
      console.log("An error occurred: " + err)
      return res.send(err);
    } 

    console.log("Success!");
    res.send(result)
  })
})

Answer 4

To define a callback function directly within your post method, you can utilize an arrow function like so:

router.post('/publicUser/getByUserID', (req, res) => {
  let userID = req.body.userID;
  User.findOne({
    userID: userID
  }, function(err, result) {
    if (err) {
      console.log("An error occurred: " + err)
      return res.send(err);
    } 

    console.log("Success!");
    res.send(result)
  })
})

RetrieveByUserIdentifier as a callback method (express)

Answer №1

Answer №2

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