koa2-ensure-login

This is a port of jaredhanson/connect-ensure-login to Koa 2

This middleware ensures that a user is logged in. If a request is received that is unauthenticated, the request will be redirected to a login page. The URL will be saved in the session, so the user can be conveniently returned to the page that was originally requested.

Install

$ npm install koa2-ensure-login

Usage

Ensure Authentication

In this example, an application has a settings page where preferences can be configured. A user must be logged in before accessing this page.

app.use(ensureLoggedIn('/login'));
app.use(function(ctx) {
  ctx.render('profile', { user: req.user });
});
  

If a user is not logged in when attempting to access this page, the request will be redirected to /login and the original request URL (/settings) will be saved to the session at req.session.returnTo.

Log In and Return To

This middleware integrates seamlessly with Passport.

To use with koa, you may find rkusa/koa-passport is more useful.

Simply mount Passport's authenticate() middleware at the login route.

router.get('/login', function(ctx) {
  ctx.render('login');
});

router.post('/login', passport.authenticate('local', { successReturnToOrRedirect: '/', failureRedirect: '/login' }));

Upon log in, Passport will notice the returnTo URL saved in the session and redirect the user back to /settings.

Step By Step

If the user is not logged in, the sequence of requests and responses that take place during this process can be confusing. Here is a step-by-step overview of what happens:

1. User navigates to GET /profile
   • Middleware sets session.returnTo to /profile
   • Middleware redirects to /login
2. User's browser follows redirect to GET /login
   • Application renders a login form (or, alternatively, offers SSO)
3. User submits credentials to POST /login
   • Application verifies credentials
   • Passport reads session.returnTo and redirects to /profile
4. User's browser follows redirect to GET /profile
   • Now authenticated, application renders profile page

License

The MIT License