mongoose-i18n-error

mongoose-i18n-error is a lightweight module for node.js/express.js to create beautiful mongoose i18n validation error messages. It is built on top of the awesome i18n-node translation module.

I never liked the mongoose/mongo error messages caused by mongoose validation or duplicate keys. So I decided to write a simple express middleware module to create consistent error messages with i18n support.

{
	username: {
		type: 'required',
		message: 'is required',
		value: undefined
	},
	email: {
		type: 'regexp',
		message: 'is no valid email',
		value: 'johndoe.de'
	}
}

Usage

npm install mongoose-i18n-error

Configure your app to support i18n:

var i18n = require('i18n');

i18n.configure({
	locales: ['en', 'de'],
	directory: './locales'
});

app.use(i18n.init);

Then, simply add the module as an express error handler middleware:

var i18nMongooseError = new (require('mongoose-i18n-error'))();

app.use(i18nMongooseError.handler(function(err, req, res, next) {
	res.status(422).json(err);
}));

Options

By default, the plugin will prefix the error messages in your locale files with 'error.':

"error.required": "is required",
"error.minlength": "needs a minimum length of %s",
"error.user.password.regexp": "is no valid email",
"error.cast": "is not valid"

You can change the prefix by passing the prefix attribute as options:

var i18nMongooseError = new (require('mongoose-i18n-error'))({
	prefix: 'err.'
});

Custom validators

In your custom mongoose validators your error message should now apply to the key in your locales.

var Schema = new mongoose.Schema({
	name: {
		type: String,
		validate: {
			validator: function(v) {
				return /^[A-Z]*$/i.test(v);
			},
			message: 'user.name.alpha'	// or 'alpha'
		}
	}
});

Tests

To run the tests you need a local MongoDB instance available. Run with:

npm test

Issues

Please use the GitHub issue tracker to raise any problems or feature requests.

If you would like to submit a pull request with any changes you make, please feel free!