@medley/cookie

Medley plugin for parsing and setting cookies.

Installation

npm install @medley/cookie
# or
yarn add @medley/cookie

Usage

const medley = require('@medley/medley');
const app = medley();

app.register(require('@medley/cookie'));

app.get('/', (req, res) => {
  if (req.cookies.foo === undefined) {
    res.setCookie('foo', 'bar');
    res.send('cookie set');
  } else {
    res.send(`cookie: foo = ${req.cookies.foo}`);
  }
});

Plugin Options

secret

Type: string

Used for signing/unsigning cookies.

app.register(require('@medley/cookie'), {
  secret: 'to everybody', // `secret` should be a long, random string
});

app.get('/', (req, res) => {
  if (req.cookies.foo === undefined) {
    const fooCookie = res.signCookie('foo-value')
    res.setCookie('foo', foo);
    res.send('cookie set');
  } else {
    const fooCookie = req.unsignCookie(req.cookies.foo);
    res.send(`foo = ${fooCookie}`);
  }
});

decode

Type: function
Default: decodeURIComponent

A function that will be used to decode each cookies' value.

app.register(require('@medley/cookie'), {
  decode: require('safe-decode-uri-component'),
});

API

• req.cookies
• req.unsignCookie(value)
• res.signCookie(value)
• res.setCookie(name, value[, options])
  • Options
• res.clearCookie(name[, options])

req.cookies

An object of parsed cookies.

app.get('/', (req, res) => {
  req.cookies // { cookieName: 'cookieValue', foo: 'bar' }
});

req.unsignCookie(value)

• value (string) - A cookie value.
• Returns (string | false) - The original cookie value (before signing) or false if the cookie was tampered with.

Unsigns a cookie value.

const fooCookie = req.unsignCookie(req.cookies.foo);
console.log(fooCookie); // 'bar'

const tamperedFooCookie = req.unsignCookie(req.cookies.foo + 'str');
console.log(tamperedFooCookie); // false

res.signCookie(value)

• value (string) - A cookie value.
• Returns (string) - The signed cookie value.

Signs a cookie value.

const signedValue = res.signCookie('hello');
console.log(signedValue); // 'hello.DGDUkGlIkCzPz+C0B064FNgHdEjox7ch8tOBGslZ5QI'

res.setCookie('greeting', signedValue);

The signed value will be different depending on the secret option used when registering the plugin.

res.setCookie(name, value[, options])

• name (string) - The name of the cookie.
• value (string) - The cookie value.
• options (object) - See the options below.
• chainable

Sets a cookie with name to value.

res.setCookie('foo', 'bar');

// Sets a cookie that expires in 1 hour
res.setCookie('rememberme', 'true', { maxAge: 3600, httpOnly: true, secure: true });

// Default encode option
res.setCookie('cross_domain_cookie', 'value!', {
  domain: 'example.com'
});
// Result: 'cross_domain_cookie=value!; Domain=example.com; Path=/'

// Custom encode option
res.setCookie('cross_domain_cookie', 'value!', {
  domain: 'example.com',
  encode: require('strict-uri-encode') // https://www.npmjs.com/package/strict-uri-encode
});
// Result: 'cross_domain_cookie=value%21; Domain=example.com; Path=/;'

Options

Property	Type	Description
domain	string	Domain name for the cookie.
encode	function	A synchronous function used for encoding the cookie value. Default: encodeURIComponent
expires	Date	Expiry date of the cookie in GMT. If not specified (and maxAge is not specified), a session cookie is created.
httpOnly	boolean	Flags the cookie to be accessible only by the web server (and not by JavaScript in the browser). Default: false
maxAge	number	Convenient option for setting the expiry time relative to the current time in seconds. If not specified (and expires is not specified), a session cookie is created.
path	string	URL path prefix at which the cookie will be available. Default: '/'
sameSite	string|boolean	Value for the SameSite Set-Cookie attribute. Can be any of the values supported by the cookie module: true, false, 'strict', 'lax', 'none'.
secure	boolean	Flags the cookie to be used with HTTPS only. Default: false

res.clearCookie(name[, options])

• name (string) - The name of a cookie.
• options (object) - See the options above.
• chainable

Clears a previously set cookie with name.

Note that for the cookie to be cleared, the domain, httpOnly, path, sameSite, and secure options must be the same as when the cookie was originally set.

res.clearCookie('foo');
res.clearCookie('rememberme', { httpOnly: true, secure: true });