How do I implement OAuth in a MEAN stack application?

How do I implement OAuth in a MEAN stack application?

To implement OAuth in a MEAN stack, you'll need to set up an authentication server, configure your app, and use libraries like Passport.js.

What libraries do I need for this?

You will primarily need Passport.js for authentication, along with Mongoose for MongoDB interactions and Express for your server.

Can you give me a basic code example?

Sure! Here's a simple example:

const passport = require('passport');
const OAuth2Strategy = require('passport-oauth2');

passport.use(new OAuth2Strategy({
  authorizationURL: 'https://provider.com/oauth2/authorize',
  tokenURL: 'https://provider.com/oauth2/token',
  clientID: 'your-client-id',
  clientSecret: 'your-client-secret',
  callbackURL: 'http://localhost:3000/auth/provider/callback'
}, function(accessToken, refreshToken, profile, done) {
  // User authentication logic here
}));

What are the common pitfalls to avoid?

Common pitfalls include not validating tokens properly, failing to secure your client secrets, and not handling user sessions correctly.