What is cookie-session?
The cookie-session npm package is a simple middleware for managing session data using cookies. It stores session data on the client within a cookie, making it stateless and lightweight. This package is particularly useful for small to medium-sized applications where server-side session storage is not necessary.
What are cookie-session's main functionalities?
Basic Session Management
This code demonstrates basic session management using cookie-session. It sets up an Express application with cookie-session middleware, which stores session data in a cookie. The session data includes the number of views for the root URL.
const express = require('express');
const cookieSession = require('cookie-session');
const app = express();
app.use(cookieSession({
name: 'session',
keys: ['key1', 'key2'],
maxAge: 24 * 60 * 60 * 1000 // 24 hours
}));
app.get('/', (req, res) => {
req.session.views = (req.session.views || 0) + 1;
res.send(`Number of views: ${req.session.views}`);
});
app.listen(3000, () => {
console.log('Server is running on port 3000');
});
Custom Cookie Options
This code demonstrates how to customize cookie options with cookie-session. It includes options like httpOnly and secure to enhance security by ensuring the cookie is only accessible via HTTP(S) and only used over HTTPS.
const express = require('express');
const cookieSession = require('cookie-session');
const app = express();
app.use(cookieSession({
name: 'session',
keys: ['key1', 'key2'],
maxAge: 24 * 60 * 60 * 1000, // 24 hours
httpOnly: true, // Ensures the cookie is only accessible via HTTP(S), not JavaScript
secure: true // Ensures the cookie is only used over HTTPS
}));
app.get('/', (req, res) => {
req.session.views = (req.session.views || 0) + 1;
res.send(`Number of views: ${req.session.views}`);
});
app.listen(3000, () => {
console.log('Server is running on port 3000');
});
Clearing Session Data
This code demonstrates how to clear session data using cookie-session. By setting req.session to null, the session data is cleared, effectively logging the user out.
const express = require('express');
const cookieSession = require('cookie-session');
const app = express();
app.use(cookieSession({
name: 'session',
keys: ['key1', 'key2'],
maxAge: 24 * 60 * 60 * 1000 // 24 hours
}));
app.get('/logout', (req, res) => {
req.session = null; // Clears the session data
res.send('Logged out');
});
app.listen(3000, () => {
console.log('Server is running on port 3000');
});
Other packages similar to cookie-session
express-session
express-session is a popular session middleware for Express that stores session data on the server side. It supports various storage options like in-memory, Redis, MongoDB, etc. Unlike cookie-session, express-session is more suitable for larger applications where server-side session storage is necessary.
client-sessions
client-sessions is another middleware for managing session data using cookies. It provides more advanced features like encryption and tamper detection. Compared to cookie-session, client-sessions offers enhanced security features but may be more complex to set up.
cookie-parser
cookie-parser is a middleware for parsing cookies attached to the client request object. While it does not manage sessions directly, it can be used in conjunction with other session management libraries. It provides more control over cookie parsing and is often used alongside express-session.
cookie-session
Simple cookie-based session middleware.
A user session can be stored in two main ways with cookies: on the server or on
the client. This module stores the session data on the client within a cookie,
while a module like express-session
stores only a session identifier on the client within a cookie and stores the
session data on the server, typically in a database.
The following points can help you choose which to use:
cookie-session
does not require any database / resources on the server side,
though the total session data cannot exceed the browser's max cookie size.cookie-session
can simplify certain load-balanced scenarios.cookie-session
can be used to store a "light" session and include an identifier
to look up a database-backed secondary store to reduce database lookups.
Semantics
This module provides "guest" sessions, meaning any visitor will have a session,
authenticated or not. If a session is new a Set-Cookie
will be produced regardless
of populating the session.
Install
$ npm install cookie-session
API
var cookieSession = require('cookie-session')
cookieSession(options)
Create a new cookie session middleware with the provided options.
Options
Cookie session accepts these properties in the options object.
name
The name of the cookie to set, defaults to express:sess
.
keys
The list of keys to use to sign & verify cookie values. Set cookies are always
signed with keys[0]
, while the other keys are valid for verification, allowing
for key rotation.
secret
A string which will be used as single key if keys
is not provided.
Cookie Options
Other options are passed to cookies.get()
and cookies.set()
allowing you
to control security, domain, path, and signing among other settings.
The options can also contain any of the following (for the full list, see
cookies module documentation:
maxAge
: a number representing the milliseconds from Date.now()
for expiryexpires
: a Date
object indicating the cookie's expiration date (expires at the end of session by default).path
: a string indicating the path of the cookie (/
by default).domain
: a string indicating the domain of the cookie (no default).secure
: a boolean indicating whether the cookie is only to be sent over HTTPS (false
by default for HTTP, true
by default for HTTPS).secureProxy
: a boolean indicating whether the cookie is only to be sent over HTTPS (use this if you handle SSL not in your node process).httpOnly
: a boolean indicating whether the cookie is only to be sent over HTTP(S), and not made available to client JavaScript (true
by default).signed
: a boolean indicating whether the cookie is to be signed (true
by default).overwrite
: a boolean indicating whether to overwrite previously set cookies of the same name (true
by default).
req.session
Represents the session for the given request.
.isNew
Is true
if the session is new.
.populated
Determine if the session has been populated with data or is empty.
req.sessionOptions
Represents the session options for the current request. These options are a
shallow clone of what was provided at middleware construction and can be
altered to change cookie setting behavior on a per-request basis.
Destroying a session
To destroy a session simply set it to null
:
req.session = null
Example
Simple view counter example
var cookieSession = require('cookie-session')
var express = require('express')
var app = express()
app.set('trust proxy', 1)
app.use(cookieSession({
name: 'session',
keys: ['key1', 'key2']
}))
app.use(function (req, res, next) {
req.session.views = (req.session.views || 0) + 1
res.end(req.session.views + ' views')
})
app.listen(3000)
Per-user sticky max age
var cookieSession = require('cookie-session')
var express = require('express')
var app = express()
app.set('trust proxy', 1)
app.use(cookieSession({
name: 'session',
keys: ['key1', 'key2']
}))
app.use(function (req, res, next) {
req.sessionOptions.maxAge = req.session.maxAge || req.sessionOptions.maxAge
})
License
MIT