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🗄️ DatabasesMongoDB

Handle cast error on find when objectId is invalid

Freshover 8 years ago
Mar 14, 20260 views
Confidence Score81%
81%

Problem

Do you want to request a feature or report a bug? Bug What is the current behavior? I'm trying to find an item by its _id, but when I try to handle the possible "error", when the client sends an id that doesn't exist and then return it as an user friendly error, it's getting into the "catch" function and resulting in an Error 500 to the user with a very big error message. I tried to find a method to handle it on google and even here, but I didn't find anything. If the current behavior is a bug, please provide the steps to reproduce. [code block] What is the expected behavior? I want to handle this kind of "error" that for me isn't an error. It's just an invalid item to search. Please mention your node.js, mongoose and MongoDB version.* Node: v7.4.0 Mongoose: 4.10.5 MongoDB: v3.4.4

Error Output

Error 500 to the user with a very big error message.

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1 Fix

Canonical Fix
High Confidence Fix
76% confidence100% success rate4 verificationsLast verified Mar 14, 2026

Solution: Handle cast error on find when objectId is invalid

Low Risk

This is expected behavior and your way of handling the error is mostly correct. I'd recommend instead doing: [code block] Checking for `instanceof CastError` is more robust because the error message may change. If you don't want to execute this check for every `find` operation you can use error handling middleware to transform the error into something that is appropriate for your application.

76

Trust Score

4 verifications

100% success
  1. 1

    This is expected behavior and your way of handling the error is mostly correct.

    This is expected behavior and your way of handling the error is mostly correct. I'd recommend instead doing:

  2. 2

    Checking for `instanceof CastError` is more robust because the error message may

    Checking for `instanceof CastError` is more robust because the error message may change.

  3. 3

    If you don't want to execute this check for every `find` operation you can use e

    If you don't want to execute this check for every `find` operation you can use error handling middleware to transform the error into something that is appropriate for your application.

Validation

Resolved in Automattic/mongoose GitHub issue #5354. Community reactions: 6 upvotes.

Verification Summary

Worked: 4
Partial: 1
Last verified Mar 14, 2026

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Environment

Submitted by

AC

Alex Chen

2450 rep

Tags

mongoosemongodbodmwon't-fix