Custom Error Messages Using Mongoose

Question

So, according to mongoose docs , you should set up a custom error message in the schema as follows:

var breakfastSchema = new Schema({ eggs: { type: Number, min: [6, 'Too few eggs'], max: 12 }, bacon: { type: Number, required: [true, 'Why no bacon?'] } }); 

So, I wanted to do something like this:

 var emailVerificationTokenSchema = mongoose.Schema({ email: {type: String, required: true, unique: [true, "email must be unique"]}, token: {type: String, required: true}, createdAt: {type: Date, required: true, default: Date.now, expires: '4h'} }); 

The idea is that when you try to save one of these tokens, and there is already a conflict, he deflates an error message stating that "the letter must be unique."

However, when I do something like this (where I save the token with the same email address):

 verificationToken.save( function (err) { if (err) { return console.log(err); } else { return console.log(err); } }); 

I keep getting the following:

 'E11000 duplicate key error: index ___.emailVerificationToken.$email_1 dup key: { : " [e-mail] 

Any thoughts? Unique parameter not supported for custom messages? Is this a viable way to go about things?

Answer 1

Unique parameter not supported for custom messages?

Uniqueness in Mongoose is not a validation parameter (e.g. required ); he tells Mongoose to create a unique index in MongoDB for this field.

The uniqueness constraint is fully processed on the MongoDB server. When you add a document with a duplicate key, the MongoDB server will return the error you are displaying ( E11000... ).

You must handle these errors yourself if you want to create personalized error messages. The Mongoose documentation (search for “Error Intermediate Tool”) provides you with an example of creating custom error handling:

 emailVerificationTokenSchema.post('save', function(error, doc, next) { if (error.name === 'MongoError' && error.code === 11000) { next(new Error('email must be unique')); } else { next(error); } }); 

(although this does not give you a specific field for which it was not possible to limit uniqueness)

Answer 2

This is not possible right away as you tried it, but you can take a look at the mongoose-unique-validator , which allows you to customize the error message if the uniqueness would be violated.

In particular, you are interested in the section on user errors .

To get what you want

"email must be unique"

he will be like this

 var uniqueValidator = require('mongoose-unique-validator'); ... emailVerificationTokenSchema.plugin(uniqueValidator, { message: '{PATH} must be unique' }); 

Answer 3

 verificationToken.save( function (err) { if (err) { return res.status(400).send({ message: (err.name === 'MongoError' && err.code === 11000) ? 'Email already exists !' : errorHandler.getErrorMessage(err) }); } else { return console.log('No Error'); } }); 

Answer 4

Updated version for Mongoose 5.xx

 MySchema.post('save', function (error, doc, next) { if (err.name === 'BulkWriteError' && error.code === 11000) next(new Error('This item already exists, please try again')); else next(error); }); 

Answer 5

You can rewrite error messages in the source, as well as in the node modules. Here is the way to go: YOUR_PROJECT / node_modules / mongoose / lib / error / validation.js

then you have no problem with the extra package for this.