Cookie Helper

The Cookie Helper provides an easy interface to manage cookies, enabling developers to set, parse, and delete cookies seamlessly.

Import

import { Hono } from 'hono'
import {
  deleteCookie,
  getCookie,
  getSignedCookie,
  setCookie,
  setSignedCookie,
  generateCookie,
  generateSignedCookie,
} from 'hono/cookie'

Usage

Regular cookies

app.get('/cookie', (c) => {
  setCookie(c, 'cookie_name', 'cookie_value')
  const yummyCookie = getCookie(c, 'cookie_name')
  deleteCookie(c, 'cookie_name')
  const allCookies = getCookie(c)
  // ...
})

Signed cookies

NOTE: Setting and retrieving signed cookies returns a Promise due to the async nature of the WebCrypto API, which is used to create HMAC SHA-256 signatures.

app.get('/signed-cookie', (c) => {
  const secret = 'secret' // make sure it's a large enough string to be secure

  await setSignedCookie(c, 'cookie_name0', 'cookie_value', secret)
  const fortuneCookie = await getSignedCookie(
    c,
    secret,
    'cookie_name0'
  )
  deleteCookie(c, 'cookie_name0')
  // `getSignedCookie` will return `false` for a specified cookie if the signature was tampered with or is invalid
  const allSignedCookies = await getSignedCookie(c, secret)
  // ...
})

Cookie Generation

generateCookie and generateSignedCookie functions allow you to create cookie strings directly without setting them in the response headers.

generateCookie

// Basic cookie generation
const cookie = generateCookie('delicious_cookie', 'macha')
// Returns: 'delicious_cookie=macha; Path=/'

// Cookie with options
const cookie = generateCookie('delicious_cookie', 'macha', {
  path: '/',
  secure: true,
  httpOnly: true,
  domain: 'example.com',
})

generateSignedCookie

// Basic signed cookie generation
const signedCookie = await generateSignedCookie(
  'delicious_cookie',
  'macha',
  'secret chocolate chips'
)

// Signed cookie with options
const signedCookie = await generateSignedCookie(
  'delicious_cookie',
  'macha',
  'secret chocolate chips',
  {
    path: '/',
    secure: true,
    httpOnly: true,
  }
)

Note: Unlike setCookie and setSignedCookie, these functions only generate the cookie strings. You need to manually set them in headers if needed.

Options

setCookie & setSignedCookie

• domain: string
• expires: Date
• httpOnly: boolean
• maxAge: number
• path: string
• secure: boolean
• sameSite: 'Strict' | 'Lax' | 'None'
• priority: 'Low' | 'Medium' | 'High'
• prefix: secure | 'host'
• partitioned: boolean

Example:

// Regular cookies
setCookie(c, 'great_cookie', 'banana', {
  path: '/',
  secure: true,
  domain: 'example.com',
  httpOnly: true,
  maxAge: 1000,
  expires: new Date(Date.UTC(2000, 11, 24, 10, 30, 59, 900)),
  sameSite: 'Strict',
})

// Signed cookies
await setSignedCookie(
  c,
  'fortune_cookie',
  'lots-of-money',
  'secret ingredient',
  {
    path: '/',
    secure: true,
    domain: 'example.com',
    httpOnly: true,
    maxAge: 1000,
    expires: new Date(Date.UTC(2000, 11, 24, 10, 30, 59, 900)),
    sameSite: 'Strict',
  }
)

deleteCookie

• path: string
• secure: boolean
• domain: string

Example:

deleteCookie(c, 'banana', {
  path: '/',
  secure: true,
  domain: 'example.com',
})

deleteCookie returns the deleted value:

const deletedCookie = deleteCookie(c, 'delicious_cookie')

__Secure- and __Host- prefix

The Cookie helper supports __Secure- and __Host- prefix for cookies names.

If you want to verify if the cookie name has a prefix, specify the prefix option.

const securePrefixCookie = getCookie(c, 'yummy_cookie', 'secure')
const hostPrefixCookie = getCookie(c, 'yummy_cookie', 'host')

const securePrefixSignedCookie = await getSignedCookie(
  c,
  secret,
  'fortune_cookie',
  'secure'
)
const hostPrefixSignedCookie = await getSignedCookie(
  c,
  secret,
  'fortune_cookie',
  'host'
)

Also, if you wish to specify a prefix when setting the cookie, specify a value for the prefix option.

setCookie(c, 'delicious_cookie', 'macha', {
  prefix: 'secure', // or `host`
})

await setSignedCookie(
  c,
  'delicious_cookie',
  'macha',
  'secret choco chips',
  {
    prefix: 'secure', // or `host`
  }
)

Following the best practices

A New Cookie RFC (a.k.a cookie-bis) and CHIPS include some best practices for Cookie settings that developers should follow.

• RFC6265bis-13
  • Max-Age/Expires limitation
  • __Host-/__Secure- prefix limitation
• CHIPS-01
  • Partitioned limitation

Hono is following the best practices. The cookie helper will throw an Error when parsing cookies under the following conditions:

• The cookie name starts with __Secure-, but secure option is not set.
• The cookie name starts with __Host-, but secure option is not set.
• The cookie name starts with __Host-, but path is not /.
• The cookie name starts with __Host-, but domain is set.
• The maxAge option value is greater than 400 days.
• The expires option value is 400 days later than the current time.