chat.io | A Real Time Chat Application built using Node.js , Express | Application Framework library

The configurations on production will be assigned from Environment Variables on Heroku, while the development configurations reside inside app/config/config.json file. You need to create a database on MongoLab, then create a database user, get the MongoDB URI, and assign it to dbURI. You need to register a new application on both Facebook and Twitter to get your tokens by which users can grant access to your application, and login using their social accounts. Now, you can assign the App ID to facebookClientID, and App Secret to facebookClientSecret. Now, you can assign the Consumer Key to twitterConsumerKey, and Consumer Secret to twitterConsumerSecret. The session needs a random string to make sure the session id in the browser is random. That random string is used to encrypt the session id in the browser, Why? To prevent session id guessing.
Go to Facebook Developers
Add new app, and fill the required information.
Get your App ID, App Secret.
Go to Add Product -> Facebook Login -> Valid OAuth redirect URIs
Add Valid Callback URIs
Go to App Review -> Make your application public.
Go to Twitter Apps
Create new app, and fill the required information.
Add Website & Callback URL
Get your Consumer Key, Consumer Secret.
It can point back to your localhost; http://localhost:3000/auth/facebook/callback
When deploy to Heroku, you will have something look like this; http://my-chat-app.herokuapp.com/auth/facebook/callback