alt-session

Redis-backed sessions for Express

This module provides your apps with asynchronous Session API with data stored in Redis.

The asynchronous approach allows you to access session data on-demand, instead of saving-restoring it on every request regardless of whether data is actually being used or not. It is also super-friendly to asynchronous control flow libraries (like async).

Usage

1. npm install alt-session

2. Add middleware after cookie parser:

   app.use(require('alt-session', {
     redis: {
       host: 'localhost',
       port: 6390,
       auth_pass: 'optional'
     },
     session: {
       dbIndex: 0,         // for selecting Redis database
       tti: 300,           // time to idle before session is removed from Redis, in seconds
       prefix: 'sess',     // custom key prefix for Redis storage
       secure: true,       // for setting cookie.secure option
       domain: 'optional'  // for custom cookie domain
     }
   }));
   

3. Store session data:

   req.session.set('myKey', 'myValue', function(err) {
     if (err)
       return next(err);
     // Success
   });
   

4. Retrieve single key:

   req.session.get('myKey', function(err, myValue) {
     if (err)
       return next(err);
     // Success
   });
   

5. Retrieve multiple keys:

   req.session.mget(['myKey1', 'myKey2'], function(err, session) {
     if (err)
       return next(err);
     // Success
     // session.myKey1
     // session.myKey2
   });
   

6. Remove single value:

   req.session.remove('myKey', function(err) {
     if (err)
       return next(err);
     // Success
   });
   

7. Remove all values:

   req.session.remove(['myKey1', 'myKey2'], function(err) {
     if (err)
       return next(err);
     // Success
   });
   

8. Invalidate (clear):

   req.session.invalidate(function(err) {
     if (err)
       return next(err);
     // Success
   });
   

Compatibility with synchronous API

Asynchronous Session API is generally incompatible with synchronous version.

If your library depends on certain keys being available in req.session, you might want to add simple middleware like this:

// Retrieve stuff
app.use(function(req, res, next) {
  req.session.get('myKey', function(value) {
    req.session.myKey = value;
    next();
  });
});

// Include your other middleware and routes

// Persist stuff
app.use(function(req, res, next) {
  req.session.set('myKey', req.session.myKey, next);
});