addywaddy / authome

A dependency-free mutli-service authentication tool for node.js

Authome

Authome is an authentication library for node.js. It unifies authentication APIs for multiple services into a single EventEmitter.

Authome was designed to solve one problem and solve it well. It has an intuitive node.js-like API, no external dependencies, and doesn't force any particular persistence, session, middleware approaches on you.

Authome currently supports Github, Google, and Facebook.

Authome is pronounced [ˈôTHəm], like "awesome" while holding your tongue.

Example

// Like socket.io, Authome will intercept requests
// for you to help keep your routes clean.

var server = require("http").createServer()
  , authome = require("authome")

server.on("request", function() {
  // your usual server logic
})

authome.createServer({ /* facebook credentials */ })
authome.createServer({ /* github credentials */ })
authome.createServer({ /* google credentials */ }) 

authome.on("auth", function(req, res, data) {
  // called when a user is authenticated on any service
})

authome.on("error", function(req, res, data) {
  // called when an error occurs during authentication
})

authome.listen(server)
server.listen(8000)

Installation and Setup

To install, enter:

$ npm install authome

To see the demo, enter:

$ sudo npm start authome

And then head to http://authome.jedschmidt.com (which resolves to your local machine at 127.0.0.1). sudo is needed to bind to port 80, as many providers do not allow callback URLs with a port or localhost as the host.

Supported services

• Github
• Google
• Facebook

FAQ

How can I add my own service?

See Extending Authome below.

Why not just use everyauth? How is Authome different?

Authome aims to solve a smaller problem, more agnostically. It trades convenience for simplicity and flexibility. Here are some key differences:

• Authome was built for node, while everyauth was built for Express and Connect. everyauth aims for a much more ambitious integration, but at the expense of locking you into a particular stack. Authome takes a more UNIX approach; since it doesn't handle logins, persistence, sessions, or anything past authentication, it is more of a tool and less of a framework.

• Authome uses native node.js conventions such as EventEmitters and objects, while everyauth uses promises and a chaining config API. This is of course subjective, but the Authome API aims to be closer to the APIs of node.js itself.

• Authome works with node.js v0.6. (this was not true of everyauth at the time this library was written)

API

authome.createServer(options, [function(req, res){}])

Creates an EventEmitter for the given authentication service. The service is specified by the service key of the options object, with all other keys differing based on the service. For example, github would be called like this:

var github = authome.createServer({
  service: "github",
  id: "7e38d12b740a339b2d31",
  secret: "116e41bd4cd160b7fae2fe8cc79c136a884928c3",
  scope: ["gist"]
})

You can listen for auth and error events by:

• listening to a specific service for service-specific events, or
• listening to authome for all service events

For example, use this to listen for events from Github, based on the code above:

github.on("auth", function(req, res, gitHubSpecificData){})
github.on("error", function(req, res, gitHubSpecificData){})

Or, use this to listen to events from all provders, since authome already listens and namespaces them for you:

authome.on("auth", function(req, res, data){})
authome.on("error", function(req, res, data){})

authome.on("auth", function(req, res, data){})

Listens for successful authentications across all services. The listener is called with the original request/response objects as well as a service-specific user object, allowing you to provide your own session scheme. The name of the service is given in the service key so that you can branch your own code:

authome.on("auth", function(req, res, data) {
  switch(data.service) {
    case "github": ...
    case "google": ...
    .
    .
    .
  }
})

authome.on("error", function(req, res, data){})

Listens for failed authentications across all services. Like the auth event, the listener is called with the original request/response objects as well as an error object, allowing you to provide your own session scheme.

authome.listen(server)

Listens to an existing HTTP(S) server for request events. Like socket.io's .listen method, Authome will intercept any request whose path starts with /auth.

authome.listener

A standard node.js listener. This can be used for more control over the path at which Authome is used. For example, the following two are equivalent:

// socket.io-style
var server = require("http").createServer()
  , authome = require("authome")

server.on("request", function() {
  /* your usual server logic */
})

authome.listen(server)
server.listen(8000)

// route-style
var server = require("http").createServer()
  , authome = require("authome")

server.on("request", function(req, res) {
  if (req.url.slice(5) == "/auth") authome.listener(req, res)

  else {
	/* your usual server logic */
  }
})

server.listen(8000)

Providers

Github

Start off by creating an application on Github. Then, to enable Github OAuth2 authentication on your site, call authome.createServer with the Github-specific options:

• service: "github"
• id: the application's Client ID
• secret: the application's Secret
• scope (optional): the scopes requested by your application, as explained here.

var github = authome.createServer({
  service: "github",
  id: "7e38d12b740a339b2d31",
  secret: "116e41bd4cd160b7fae2fe8cc79c136a884928c3",
  scope: ["gist"]
})

Make sure that the callback URL used by your application has the same hostname and port as that specified for your application. If they are different, you will get redirect_uri_mismatch errors.

Google

Start off by creating an application on Google. Then, to enable Google OAuth2 authentication on your site, call authome.createServer with the Google-specific options:

• service: "google"
• id: the application's Client ID
• secret: the application's Client secret
• scope (optional): the scopes requested by your application

var google = authome.createServer({
  service: "google",
  id: "515913292583.apps.googleusercontent.com",
  secret: "UAjUGd_MD9Bkho-kazmJ5Icm",
  scope: ""
})

Make sure that the callback URL used by your application is identical to that specified for your application. With the default settings, you'll need a redirect URI of http://<your-host>/auth?service=google.

Facebook

Start off by creating an application on Facebook. Then, to enable Facebook OAuth2 authentication on your site, call authome.createServer with the Facebook-specific options:

• service: "facebook"
• id: the application's App ID
• secret: the application's App secret
• scope (optional): the scopes requested by your application

var facebook = authome.createServer({
  service: "facebook",
  id: "256546891060909",
  secret: "e002572fb07423fa66fc38c25c9f49ad",
  scope: []
})

Extending Authome

To add an authentication service provider, add a javascript file for the service at the path /lib/services/<service-name>.js. This file should module.export a single function.

module.exports = function(options) {
  var server = this // an event emitter specific to this service

  server.on("request", function(req, res) {
    // respond to the request, redirecting the user as needed

    if (successful) {
      // pass an object containing the service's user data
      server.emit("auth", req, res, obj)
    }

    else {
      // pass an object containing an error message
      server.emit("error", req, res, obj)
    }
  })
}

To make sure that your code can recieve subsequent HTTP(S) calls from the service, use the inbound req.url as the callback URL, using the querystring to disambiguate different stages of the authentication process. See /lib/services/github.js for an example implementation.

Once you're done, and have written tests, make sure you open a pull request so that the rest of us can benefit!

License

Copyright (c) 2011 Jed Schmidt, http://jed.is/

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.