next-session
Lightweight promise-based session middleware for Next.js. Also works in micro or Node.js HTTP Server, Express, and more.
Also check out alternatives like next-iron-session. Take a look at nextjs-mongodb-app to see this module in use.
Installation
// NPM
npm install next-session
// Yarn
yarn add next-session
Usage
Warning The default session store (if options?.store
is undefined
), MemoryStore
, DOES NOT work in production or serverless environment. You must use a Session Store.
// ./lib/get-session.js
import nextSession from "next-session";
export const getSession = nextSession(options);
API Routes
import { getSession } from "./lib/get-session.js";
export default function handler(req, res) {
const session = await getSession(req, res);
session.views = session.views ? session.views + 1 : 1;
// Also available under req.session:
// req.session.views = req.session.views ? req.session.views + 1 : 1;
res.send(
`In this session, you have visited this website ${session.views} time(s).`
);
}
Usage in API Routes may result in API resolved without sending a response
. This can be solved by either adding:
import nextSession from "next-session";
const getSession = nextSession();
export default function handler(req, res) {
const session = await getSession(req, res);
/* ... */
}
export const config = {
api: {
externalResolver: true,
},
};
...or setting options.autoCommit
to false
and do await session.commit()
.
import nextSession from "next-session";
const getSession = nextSession({ autoCommit: false });
export default function handler(req, res) {
const session = await getSession(req, res);
/* ... */
await session.commit();
}
getServerSideProps
import { getSession } from "./lib/get-session.js";
export default function Page({ views }) {
return (
<div>In this session, you have visited this website {views} time(s).</div>
);
}
export async function getServerSideProps({ req, res }) {
const session = await getSession(req, res);
session.views = session.views ? session.views + 1 : 1;
// Also available under req.session:
// req.session.views = req.session.views ? req.session.views + 1 : 1;
return {
props: {
views: session.views,
},
};
}
Others
const express = require("express");
const app = express();
app.use(async (req, res, next) => {
await getSession(req, res); // session is set to req.session
next();
});
app.get("/", (req, res) => {
req.session.views = req.session.views ? req.session.views + 1 : 1;
res.send(
`In this session, you have visited this website ${req.session.views} time(s).`
);
});
micro, Vercel Serverless Functions
module.exports = (req, res) => {
const session = await getSession(req, res);
res.end(
`In this session, you have visited this website ${session.views} time(s).`
);
};
const http = require("http");
const server = http.createServer(async (req, res) => {
const session = await getSession(req, res);
res.end(`In this session, you have visited this website ${session.views} time(s).`;
});
server.listen(8080);
Options
next-session
accepts the properties below.
options | description | default |
---|---|---|
name | The name of the cookie to be read from the request and set to the response. | sid |
store | The session store instance to be used. Required to work in production! | MemoryStore |
genid | The function that generates a string for a new session ID. | nanoid |
encode | Transforms session ID before setting cookie. It takes the raw session ID and returns the decoded/decrypted session ID. | undefined |
decode | Transforms session ID back while getting from cookie. It should return the encoded/encrypted session ID | undefined |
touchAfter | Only touch after an amount of time (in seconds) since last access. Disabled by default or if set to -1 . See touchAfter. |
-1 (Disabled) |
autoCommit | Automatically commit session. Disable this if you want to manually session.commit()
|
true |
cookie.secure | Specifies the boolean value for the Secure Set-Cookie attribute. |
false |
cookie.httpOnly | Specifies the boolean value for the httpOnly Set-Cookie attribute. |
true |
cookie.path | Specifies the value for the Path Set-Cookie attribute. |
/ |
cookie.domain | Specifies the value for the Domain Set-Cookie attribute. |
unset |
cookie.sameSite | Specifies the value for the SameSite Set-Cookie attribute. |
unset |
cookie.maxAge |
(in seconds) Specifies the value for the Max-Age Set-Cookie attribute. |
unset (Browser session) |
touchAfter
Touching refers to the extension of session lifetime, both in browser (by modifying Expires
attribute in Set-Cookie header) and session store (using its respective method) upon access. This prevents the session from being expired after a while.
In autoCommit
mode (which is enabled by default), for optimization, a session is only touched, not saved, if it is not modified. The value of touchAfter
allows you to skip touching if the session is still recent, thus, decreasing database load.
encode/decode
You may supply a custom pair of function that encode/decode or encrypt/decrypt the cookie on every request.
// `express-session` signing strategy
const signature = require("cookie-signature");
const secret = "keyboard cat";
session({
decode: (raw) => signature.unsign(raw.slice(2), secret),
encode: (sid) => (sid ? "s:" + signature.sign(sid, secret) : null),
});
API
session object
This allows you to set or get a specific value that associates to the current session.
// Set a value
if (loggedIn) session.user = "John Doe";
// Get a value
const currentUser = session.user; // "John Doe"
session.touch()
Manually extends the session expiry by maxAge. Note: You must still call session.commit() if autoCommit = false
.
session.touch();
If touchAfter
is set with a non-negative value, this will be automatically called accordingly.
session.destroy()
Destroy to current session and remove it from session store.
if (loggedOut) await session.destroy();
session.commit()
Save the session and set neccessary headers. Return Promise. It must be called before sending the headers (res.writeHead
) or response (res.send
, res.end
, etc.).
You must call this if autoCommit
is set to false
.
session.hello = "world";
await session.commit();
// always calling res.end or res.writeHead after the above
session.id
The unique id that associates to the current session.
Session Store
The session store to use for session middleware (see options
above).
Implementation
A compatible session store must include three functions: set(sid, session)
, get(sid)
, and destroy(sid)
. The function touch(sid, session)
is recommended. All functions must return Promises.
Refer to MemoryStore.
TypeScript: the SessionStore
type can be used to aid implementation:
import type { SessionStore } from "next-session";
class CustomStore implements SessionStore {}
Compatibility with Express/Connect stores
Promisify functions
To use Express/Connect stores, you must promisify get
, set
, destroy
, and (if exists) touch
methods, possibly using util.promisify
.
We include the util promisifyStore
in next-session/lib/compat
to do just that:
import nextSession from "next-session";
import { promisifyStore } from "next-session/lib/compat";
import SomeConnectStore from "connect-xyz";
const connectStore = new SomeConnectStore();
const getSession = nextSession({
store: promisifyStore(connectStore),
});
You can use expressSession
from next-session/lib/compat
if the connect store has the following pattern.
const session = require("express-session");
const RedisStore = require("connect-redis")(session);
// Use `expressSession` from `next-session/lib/compat` as the replacement
import nextSession from "next-session";
import { expressSession, promisifyStore } from "next-session/lib/compat";
import RedisStoreFactory from "connect-redis";
import Redis from "ioredis";
const RedisStore = RedisStoreFactory(expressSession);
export const getSession = nextSession({
store: promisifyStore(
new RedisStore({
client: new Redis(),
})
),
});
Contributing
Please see my contributing.md.