igorescobar / mongoose-unique-validator

mongoose-unique-validator is a plugin which adds pre-save validation for unique fields within a Mongoose schema.

mongoose-unique-validator

mongoose-unique-validator is a plugin which adds pre-save validation for unique fields within a Mongoose schema.

This makes error handling much easier, since you will get a Mongoose validation error when you attempt to violate a unique constraint, rather than an E11000 error from MongoDB.

Usage

npm install mongoose-unique-validator

Then, simply apply the plugin to your schema:

var mongoose = require('mongoose');
var uniqueValidator = require('mongoose-unique-validator');

var mySchema = mongoose.Schema(/* put your schema definition here */);
mySchema.plugin(uniqueValidator);

Example

Let’s say you have a user schema. You can easily add validation for the unique constraints in this schema by applying the uniqueValidator plugin to your user schema:

var mongoose = require('mongoose');
var uniqueValidator = require('mongoose-unique-validator');

// Define your schema as normal.
var userSchema = mongoose.Schema({
    username: { type: String, required: true, unique: true },
    email: { type: String, index: true, unique: true, required: true },
    password: { type: String, required: true }
});

// Apply the uniqueValidator plugin to userSchema.
userSchema.plugin(uniqueValidator);

Now when you try to save a user, the unique validator will check for duplicate database entries and report them just like any other validation error:

var user = new User({ username: 'JohnSmith', email: '[e-mail]', password: 'j0hnNYb0i' });
user.save(function (err) {
    console.log(err);
});

{
    message: 'Validation failed',
    name: 'ValidationError',
    errors: {
        username: {
            message: 'Validator failed for path `username` with value `JohnSmith`',
            name: 'ValidatorError',
            path: 'username',
            type: 'user defined',
            value: 'JohnSmith'
        }
    }
}

Custom Error Messages

You can pass through a custom error message as part of the optional options argument:

userSchema.plugin(uniqueValidator, { message: 'Error, expected {PATH} to be unique.' });

You have access to all of the standard Mongoose error message templating:

• {PATH}
• {VALUE}
• {TYPE}