@fastify/cookie/plugin.js

Plugin for fastify to add support for cookies

'use strict'

const fp = require('fastify-plugin')
const cookie = require('cookie')

const { Signer, sign, unsign } = require('./signer')

const kReplySetCookies = Symbol('fastify.reply.setCookies')
const kReplySetCookiesHookRan = Symbol('fastify.reply.setCookiesHookRan')

function fastifyCookieSetCookie (reply, name, value, options) {
  parseCookies(reply.server, reply.request, reply)

  const opts = Object.assign({ sameSite: 'lax' }, options)

  if (opts.expires && Number.isInteger(opts.expires)) {
    opts.expires = new Date(opts.expires)
  }

  if (opts.signed) {
    value = reply.signCookie(value)
  }

  if (opts.secure === 'auto') {
    if (reply.request.protocol === 'https') {
      opts.secure = true
    } else {
      opts.secure = false
    }
  }

  reply[kReplySetCookies].set(`${name};${opts.domain};${opts.path || '/'}`, { name, value, opts })

  if (reply[kReplySetCookiesHookRan]) {
    setCookies(reply)
  }

  return reply
}

function fastifyCookieClearCookie (reply, name, options) {
  const opts = Object.assign({ path: '/' }, options, {
    expires: new Date(0),
    maxAge: 0,
    signed: false
  })

  return fastifyCookieSetCookie(reply, name, '', opts)
}

function parseCookies (fastify, request, reply) {
  if (reply[kReplySetCookies]) return

  const cookieHeader = request.raw.headers.cookie

  request.cookies = cookieHeader ? fastify.parseCookie(cookieHeader) : {} // New container per request. Issue #53
  reply[kReplySetCookies] = new Map()
}

function onReqHandlerWrapper (fastify, hook) {
  return hook === 'preParsing'
    ? function fastifyCookieHandler (fastifyReq, fastifyRes, _payload, done) {
      parseCookies(fastify, fastifyReq, fastifyRes)
      done()
    }
    : function fastifyCookieHandler (fastifyReq, fastifyRes, done) {
      parseCookies(fastify, fastifyReq, fastifyRes)
      done()
    }
}

function setCookies (reply) {
  const setCookieHeaderValue = reply.getHeader('Set-Cookie')
  let cookieValue

  if (setCookieHeaderValue === undefined) {
    if (reply[kReplySetCookies].size === 1) {
      // Fast path for single cookie
      const c = reply[kReplySetCookies].values().next().value
      reply.header('Set-Cookie', cookie.serialize(c.name, c.value, c.opts))
      reply[kReplySetCookies].clear()
      return
    }

    cookieValue = []
  } else if (typeof setCookieHeaderValue === 'string') {
    cookieValue = [setCookieHeaderValue]
  } else {
    cookieValue = setCookieHeaderValue
  }

  for (const c of reply[kReplySetCookies].values()) {
    cookieValue.push(cookie.serialize(c.name, c.value, c.opts))
  }

  reply.removeHeader('Set-Cookie')
  reply.header('Set-Cookie', cookieValue)
  reply[kReplySetCookies].clear()
}

function fastifyCookieOnSendHandler (_fastifyReq, fastifyRes, _payload, done) {
  if (!fastifyRes[kReplySetCookies]) {
    done()
    return
  }

  if (fastifyRes[kReplySetCookies].size) {
    setCookies(fastifyRes)
  }

  fastifyRes[kReplySetCookiesHookRan] = true

  done()
}

function plugin (fastify, options, next) {
  const secret = options.secret
  const hook = getHook(options.hook)
  if (hook === undefined) {
    return next(new Error('@fastify/cookie: Invalid value provided for the hook-option. You can set the hook-option only to false, \'onRequest\' , \'preParsing\' , \'preValidation\' or \'preHandler\''))
  }
  const isSigner = !secret || (typeof secret.sign === 'function' && typeof secret.unsign === 'function')
  const signer = isSigner ? secret : new Signer(secret, options.algorithm || 'sha256')

  fastify.decorate('serializeCookie', cookie.serialize)
  fastify.decorate('parseCookie', parseCookie)

  if (secret !== undefined) {
    fastify.decorate('signCookie', signCookie)
    fastify.decorate('unsignCookie', unsignCookie)

    fastify.decorateRequest('signCookie', signCookie)
    fastify.decorateRequest('unsignCookie', unsignCookie)

    fastify.decorateReply('signCookie', signCookie)
    fastify.decorateReply('unsignCookie', unsignCookie)
  }

  fastify.decorateRequest('cookies', null)
  fastify.decorateReply(kReplySetCookies, null)
  fastify.decorateReply(kReplySetCookiesHookRan, false)

  fastify.decorateReply('cookie', setCookie)
  fastify.decorateReply('setCookie', setCookie)
  fastify.decorateReply('clearCookie', clearCookie)

  if (hook) {
    fastify.addHook(hook, onReqHandlerWrapper(fastify, hook))
    fastify.addHook('onSend', fastifyCookieOnSendHandler)
  }

  next()

  // ***************************
  function parseCookie (cookieHeader) {
    return cookie.parse(cookieHeader, options.parseOptions)
  }

  function signCookie (value) {
    return signer.sign(value)
  }

  function unsignCookie (value) {
    return signer.unsign(value)
  }

  function setCookie (name, value, cookieOptions) {
    const opts = Object.assign({}, options.parseOptions, cookieOptions)
    return fastifyCookieSetCookie(this, name, value, opts)
  }

  function clearCookie (name, cookieOptions) {
    const opts = Object.assign({}, options.parseOptions, cookieOptions)
    return fastifyCookieClearCookie(this, name, opts)
  }
}

function getHook (hook = 'onRequest') {
  const hooks = {
    onRequest: 'onRequest',
    preParsing: 'preParsing',
    preValidation: 'preValidation',
    preHandler: 'preHandler',
    [false]: false
  }

  return hooks[hook]
}

const fastifyCookie = fp(plugin, {
  fastify: '5.x',
  name: '@fastify/cookie'
})

/**
 * These export configurations enable JS and TS developers
 * to consume fastify-cookie in whatever way best suits their needs.
 * Some examples of supported import syntax includes:
 * - `const fastifyCookie = require('fastify-cookie')`
 * - `const { fastifyCookie } = require('fastify-cookie')`
 * - `import * as fastifyCookie from 'fastify-cookie'`
 * - `import { fastifyCookie } from 'fastify-cookie'`
 * - `import fastifyCookie from 'fastify-cookie'`
 */
module.exports = fastifyCookie
module.exports.default = fastifyCookie // supersedes fastifyCookie.default = fastifyCookie
module.exports.fastifyCookie = fastifyCookie // supersedes fastifyCookie.fastifyCookie = fastifyCookie

module.exports.serialize = cookie.serialize
module.exports.parse = cookie.parse

module.exports.signerFactory = Signer
module.exports.Signer = Signer
module.exports.sign = sign
module.exports.unsign = unsign