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

Question

Need some help here. Tried almost everything that I found at the internet, but didn't works.

So, this is my code:

    const id = req.params.id.trim(); 
    Blog.findById(id)
        .then((result) => {
            res.render("details", { blog: result, title: "Blog Details" });
        })
        .catch((err) => {
            console.log(err);
        });
};

it's happens when I'm trying to create a new blog.

this is my error :

CastError: Cast to ObjectId failed for value "blogs" (type string) at path "_id" for model "Blog"
    at model.Query.exec (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/query.js:4546:21)
    at model.Query.Query.then (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/query.js:4645:15)
    at blog_details (/Users/xxx/blogMongoDB/controllers/blogController.js:19:10)
    at Layer.handle [as handle_request] (/Users/xxx/blogMongoDB/node_modules/express/lib/router/layer.js:95:5)
    at next (/Users/xxx/blogMongoDB/node_modules/express/lib/router/route.js:137:13)
    at Route.dispatch (/Users/xxx/blogMongoDB/node_modules/express/lib/router/route.js:112:3)
    at Layer.handle [as handle_request] (/Users/xxx/blogMongoDB/node_modules/express/lib/router/layer.js:95:5)
    at /Users/xxx/blogMongoDB/node_modules/express/lib/router/index.js:281:22
    at param (/Users/xxx/blogMongoDB/node_modules/express/lib/router/index.js:354:14)
    at param (/Users/xxx/blogMongoDB/node_modules/express/lib/router/index.js:365:14) {
  messageFormat: undefined,
  stringValue: '"blogs"',
  kind: 'ObjectId',
  value: 'blogs',
  path: '_id',
  reason: BSONTypeError: Argument passed in must be a string of 12 bytes or a string of 24 hex characters
      at new BSONTypeError (/Users/xxx/blogMongoDB/node_modules/bson/lib/error.js:41:28)
      at new ObjectId (/Users/xxx/blogMongoDB/node_modules/bson/lib/objectid.js:65:23)
      at castObjectId (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/cast/objectid.js:25:12)
      at ObjectId.cast (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/schema/objectid.js:245:12)
      at ObjectId.SchemaType.applySetters (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/schematype.js:1135:12)
      at ObjectId.SchemaType._castForQuery (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/schematype.js:1567:15)
      at ObjectId.SchemaType.castForQuery (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/schematype.js:1557:15)
      at ObjectId.SchemaType.castForQueryWrapper (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/schematype.js:1534:20)
      at cast (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/cast.js:336:32)
      at model.Query.Query.cast (/Users/xxx/blogMongoDB/node_modules/mongoose/lib/query.js:4969:12),
  valueType: 'string'
}

Answer 1

new mongoose.Types.ObjectId(req.query.sId)

Answer 2

i once had a similar problem If you have a handler app.get('/blogs/create') place it ABOVE your handler app.get('/blogs/:id').

This error is due to express trying to interpret create which is of type string in the url blogs/*create* as an id.

Answer 3

you can't transform a normal string to an ObjectId, check the param.id before use it.

you can use ObjectId.isValid("YOUR ID STRING") to test it.

Answer 4

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

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

Answer 5

Your request parameter must be a string of 12 bytes or a string of 24 hex characters Check the _id in your request params. It must be a 24 hex number such as this: 61d634706a98a61edd42bf45

This may solve your problem. It would be great if someone could provide more info about this subject.

The question is: What if the client searches for an _id that doesn't have a length of 24? Why is Mongoose throwing an error instead of just returning something like "id not found"?

Answer 6

i would suggest delete node and mongoDB and try to install again,if you have tried all method and nothing work reinstall monogdb and node .its work form me atleast tho.make sure you backup document before deleting all.good luck

Answer 7

In my case..
I was adding an object when I should have added a string.

const id = req.params

this code gave me an object, so I had to select the id inside that object.

const id = req.params.streamId;

And if it still does not work, then add .toString() at the end

Answer 8

Your handler app.get('/blogs/create') need to go ABOVE your handler app.post('/blogs/:id').

Answer 9

Convert id to ObjectId:

import { ObjectId } from "mongodb";
const convertedId = ObjectId(id)

If conversion is not successful due to invalid id, then you can catch error:

try{
   //your code
}catch(e){
   if(e instance of BSONTypeError){
      //do whatever you need if this occurs
   }
}

Don't forget to import { BSONTypeError } from "bson";

Answer 10

mongodb _id is an ObjectID therefore the mongoose need to look-up the Object and not the string.

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

Answer 11

CastError: Cast to ObjectId failed for value "blogs" ==> this means that the actual value of "const id = req.params.id.trim()" is the string "blogs" and this "blogs" is not a string of 12 bytes or a string of 24 hex characters that Blog.findById(id) is expecting.

https://mongoosejs.com/docs/schematypes.html#objectids

try to check the value of the id then make sure you're sending the correct value from the front-end

Answer 12

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

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