@seedalpha/passport-local-mongoose

Passport-Local Mongoose

Passport-Local Mongoose is a Mongoose plugin that simplifies building username and password login with Passport.

Tutorials

Michael Hermann gives a comprehensible walk through for setting up mongoose, passport, passport-local and passport-local-mongoose for user authentication in his blog post User Authentication With Passport.js

Installation

$ npm install passport-local-mongoose

Passport-Local Mongoose does not require passport, passport-local or mongoose dependencies directly but expects you to have these dependencies installed.

In case you need to install the whole set of dependencies

$ npm install passport passport-local mongoose passport-local-mongoose --save

Usage

Plugin Passport-Local Mongoose

First you need to plugin Passport-Local Mongoose into your User schema

var mongoose = require('mongoose'),
    Schema = mongoose.Schema,
    passportLocalMongoose = require('passport-local-mongoose');

var User = new Schema({});

User.plugin(passportLocalMongoose);

module.exports = mongoose.model('User', User);

You're free to define your User how you like. Passport-Local Mongoose will add a username, hash and salt field to store the username, the hashed password and the salt value.

Additionally Passport-Local Mongoose adds some methods to your Schema. See the API Documentation section for more details.

Configure Passport/Passport-Local

You should configure Passport/Passport-Local as described in the Passport Guide.

Passport-Local Mongoose supports this setup by implementing a LocalStrategy and serializeUser/deserializeUser functions.

To setup Passport-Local Mongoose use this code

// requires the model with Passport-Local Mongoose plugged in
var User = require('./models/user');

// use static authenticate method of model in LocalStrategy
passport.use(new LocalStrategy(User.authenticate()));

// use static serialize and deserialize of model for passport session support
passport.serializeUser(User.serializeUser());
passport.deserializeUser(User.deserializeUser());

Make sure that you have a mongoose connected to mongodb and you're done.

Simplified Passport/Passport-Local Configuration

Starting with version 0.2.1 passport-local-mongoose adds a helper method createStrategy as static method to your schema. The createStrategy is responsible to setup passport-local LocalStrategy with the correct options.

var User = require('./models/user');

// CHANGE: USE "createStrategy" INSTEAD OF "authenticate"
passport.use(User.createStrategy());

passport.serializeUser(User.serializeUser());
passport.deserializeUser(User.deserializeUser());

The reason for this functionality is that when using the usernameField option to specify an alternative usernameField name, for example "email" passport-local would still expect your frontend login form to contain an input field with name "username" instead of email. This can be configured for passport-local but this is double the work. So we got this shortcut implemented.

Options

When plugging in Passport-Local Mongoose plugin additional options can be provided to configure the hashing algorithm.

User.plugin(passportLocalMongoose, options);

Main Options

• saltlen: specifies the salt length in bytes. Default: 32
• iterations: specifies the number of iterations used in pbkdf2 hashing algorithm. Default: 25000
• keylen: specifies the length in byte of the generated key. Default: 512
• usernameField: specifies the field name that holds the username. Defaults to 'username'. This option can be used if you want to use a different field to hold the username for example "email".
• saltField: specifies the field name that holds the salt value. Defaults to 'salt'.
• hashField: specifies the field name that holds the password hash value. Defaults to 'hash'.
• selectFields: specifies the fields of the model to be selected from mongodb (and stored in the session). Defaults to 'undefined' so that all fields of the model are selected.
• usernameLowerCase: convert username field value to lower case when saving an querying. Defaults to 'false'.
• populateFields: specifies fields to populate in findByUsername function. Defaults to 'undefined'.
• encoding: specifies the encoding the generated salt and hash will be stored in. Defaults to 'hex'.

Error Message Options

• incorrectPasswordError: specifies the error message returned when the password is incorrect. Defaults to 'Incorrect password'.
• incorrectUsernameError: specifies the error message returned when the username is incorrect. Defaults to 'Incorrect username'.
• missingUsernameError: specifies the error message returned when the username has not been set during registration. Defaults to 'Field %s is not set'.
• missingPasswordError: specifies the error message returned when the password has not been set during registration. Defaults to 'Password argument not set!'.
• userExistsError: specifies the error message returned when the user already exists during registration. Defaults to 'User already exists with name %s'.
• noSaltValueStored: specifies the error message returned in case no salt value is stored in the mongodb collection. Defaults to 'Authentication not possible. No salt value stored in mongodb collection!'

Attention! Changing any of the hashing options (saltlen, iterations or keylen) in a production environment will prevent that existing users to authenticate!

Hash Algorithm

Passport-Local Mongoose use the pbkdf2 algorithm of the node crypto library. Pbkdf2 was chosen because platform independent (in contrary to bcrypt). For every user a generated salt value is saved to make rainbow table attacks even harder.

Examples

For a complete example implementing a registration, login and logout see the login example.

API Documentation

Instance methods

• setPassword(password, cb) asynchronous method to set a user's password hash and salt
• authenticate(password, cb) asynchronous method to authenticate a user instance

Using setPassword() will only update the document's password fields, but will not save the document. To commit the changed document, remember to use Mongoose's document.save() after using setPassword().

Static methods

Static methods are exposed on the model constructor. For example to use createStrategy function use

var User = require('./models/user');
User.createStrategy();

• authenticate() Generates a function that is used in Passport's LocalStrategy
• serializeUser() Generates a function that is used by Passport to serialize users into the session
• deserializeUser() Generates a function that is used by Passport to deserialize users into the session
• register(user, password, cb) Convenience method to register a new user instance with a given password. Checks if username is unique. See login example.
• findByUsername() Convenience method to find a user instance by it's unique username.
• createStrategy() Creates a configured passport-local LocalStrategy instance that can be used in passport.

License

Passport-Local Mongoose is licenses under the MIT license.