Sessions
Providing state to the server
HTTP is stateless
Remember, an HTTP request is just a string.
GET / HTTP/1.1
Host: localhost
Cookie: theme=light; sessionToken=abc123But I only need to log in once...
True, you only need to provide your credentials once, but how does the server remember that you've logged in?
Cookies are only a part of the whole picture.
You shouldn't trust cookie values for everything.
Data integrity
Since client information is unreliable, we use sessions to store information on our servers.
Global app state
var user = { username: 'bob', email: 'bob@example.com' };
app.get('/profile', function (req, res) {
res.render('profile', user);
});Global app state
const users = [
{ username: 'bob', email: 'bob@example.com' },
{ username: 'alice', email: 'alice@example.com' }
];
app.get('/profile', function (req, res) {
var id = req.cookies.id
res.render('profile', users[id]);
});Redis
A solution to a problem?
- Redis is an in-memory data store
- Offers persistent storage
- Fast
Sessions
By Tony Gaskell
