here is the code of mine

router.get('/:id', async (request, response) => {
    try{
        const user_obj = await User.findById(request.params.id);
        if (! user_obj) return response.status(404).send("No course found with the given id.");
        return response.send(user_obj);
    }
    catch(error){
        console.log(error);
    }
    return response.status(400).send("done.");
});

what i am trying to do is to catch the exact reason of failing which is obviously we all know object id is not correct.

i do have tried to wrap it in a try catch block and to get the error message from the error but it says

BSONTypeError: Argument passed in must be a string of 12 bytes or a string of 24 hex characters or an integer

which is not really descriptive why it is happening.

CodePudding user response：

You have to validate request.params.id before passing it to that function.

import mongoose from 'mongoose'

router.get('/:id', async (request, response) => {
  try {
    const { id } = request.params
    if (!mongoose.Types.ObjectId.isValid(id)) throw new Error('invalid id') // validating `id`

    const user_obj = await User.findById(id)
    if (!user_obj) return response.status(404).send('No course found with the given id.')
    
    response.send(user_obj)
  } catch (error) {
    console.error(error)
    // next(error)
    response.status(501).send('internal server error')
  }
})

Also you should be using response.json(...) instead of response.send(...)

CodePudding user response：

Convert the type of id from string to mongoose objectID(default for _id).

const id = mongoose.Types.ObjectId(req.params.id.trim());