mongoose-beautiful-unique-validation

mongoose-beautiful-unique-validation

Plugin for Mongoose that turns duplicate errors into regular Mongoose validation errors.

Mongoose's unicity constraint actually relies on MongoDB's unique indexes. It means that, if you have a schema like this one:

mongoose.Schema({
    name: {
        type: String,
        unique: true
    }
});

Duplicates will be reported with this kind of error:

{
    "name": "MongoError",
    "message": "insertDocument :: caused by :: 11000 E11000 duplicate key error index: example.users.$name_1 dup key: { : \"John\" }",
    "index": 0,
    "code": 11000,
    "errmsg": "insertDocument :: caused by :: 11000 E11000 duplicate key error index: example.users.$name_1 dup key: { : \"John\" }"
}

This is not the same kind of error as normal Validation errors, so you need to handle that as a special case―and special cases allow room for bugs. This plugin solves this problem by turning driver-level duplicate errors (E11000 and E11001) into regular Validation errors.

{
    "name": "ValidationError",
    "message": "Model validation failed",
    "errors": {
        "name": {
            "name":"ValidatorError",
            "properties": {
                "type": "Duplicate value",
                "message": "Custom error message",
                "path": "name",
                "value": "John"
            },
            "message": "Custom error message",
            "kind": "Duplicate value",
            "path": "name",
            "value": "John"
        }
    }
}

Install

npm install --save mongoose-beautiful-unique-validation

Supported versions of Mongoose

The 5.0.0 versions of this module only support Mongoose 4.5.0 and upper. If you need to use previous versions of Mongoose, use the 4.0.0 versions.

Supported versions of Node

The latest version of this module supports Node.js version 6.*, 5.*, 4.*, 0.12.* and 0.10.*. If you find a bug while using one of these versions, you can fill a bug report and we will take care of it as soon as possible!

Example

Saving a duplicate document

let beautifyUnique = require('mongoose-beautiful-unique-validation');
let userSchema = mongoose.Schema({
    name: {
        type: String,
        // this will be the uniqueness error message
        // leave it to "true" to keep the default one:
        unique: 'Two users cannot share the same username'
    }
});

// enables beautifying
userSchema.plugin(beautifyUnique);

// let's create two conflicting documents
let User = mongoose.model('Model', userSchema);
let admin1 = new User({
    name: 'admin'
});

let admin2 = new User({
    name: 'admin'
});

admin1.save()
    .then(() => console.log('Success saving admin1!'))
    .catch(err => console.error('admin1 could not be saved: ', err));

admin2.save()
    .then(() => console.log('Success saving admin2!'))
    .catch(err => console.error('admin2 could not be saved: ', err));

// will print:
// Success saving admin1!
// admin2 could not be saved: [ValidationError: User validation failed]

Updating a document to be a duplicate

let beautifyUnique = require('mongoose-beautiful-unique-validation');
let userSchema = mongoose.Schema({
    name: {
        type: String,
        // this will be the uniqueness error message
        // leave it to "true" to keep the default one:
        unique: 'Two users cannot share the same username'
    }
});

// enables beautifying
userSchema.plugin(beautifyUnique);

// let's create two documents
let User = mongoose.model('Model', userSchema);
let admin1 = new User({
    name: 'admin1'
});

let admin2 = new User({
    name: 'admin2'
});

// first, save both documents
Promise.all([
    admin1.save(),
    admin2.save()
]).then(() => {
    // try to update admin2 so that it is a duplicate of admin1
    admin2
        .update({
            $set: {name: 'admin1'}
        })
        .exec()
        .then(() => console.log('Success updating admin2!'))
        .catch(err => console.error('admin2 could not be updated: ', err))
}).catch(err => console.error('admin1/admin2 could not be saved: ', err));

// will print:
// admin2 could not be updated: [ValidationError: User validation failed]

Usage

Schemata that will produce beautified errors need to be plugged in with this module using the .plugin() method. You can also use it as a global plugin.

You need to plug in this module after declaring all indexes on the schema, otherwise they will not be beautified.

By default, the ValidatorError message will be Validator failed for path xxx with value xxx. If you want to override it, add your custom message in the unique field (instead of true), during the schema's creation.

The error's errors property contain a list of all original values that made the contraint fail. This property is not filled in when using findOneAndUpdate.

License

Released under the MIT license.
See the full license text.