# cookie
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[![Build Status][ci-image]][ci-url]
[![Coverage Status][coverage-image]][coverage-url]
Basic HTTP cookie parser and serializer for HTTP servers.
## Installation
```sh
$ npm install cookie
```
## API
```js
const cookie = require("cookie");
// import * as cookie from 'cookie';
```
### cookie.parseCookie(str, options)
Parse an HTTP `Cookie` header string and return an [object](#cookie-object) of all cookie name-value pairs.
The `str` argument is the string representing a `Cookie` header value and `options` is an
optional object containing additional parsing options.
```js
const cookieObject = cookie.parseCookie("foo=bar; equation=E%3Dmc%5E2");
// { foo: 'bar', equation: 'E=mc^2' }
```
#### Options
- `decode` Specifies the function to decode a [cookie-value](https://datatracker.ietf.org/doc/html/rfc6265#section-4.1.1). Defaults to [`decodeURIComponent`](#encode-and-decode).
### cookie.stringifyCookie(cookieObj, options)
Stringifies a [cookie object](#cookie-object) into an HTTP `Cookie` header.
```js
const cookieHeader = cookie.stringify({ a: "foo", b: "bar" });
// a=foo; b=bar
```
#### Options
- `encode` Specifies the function to encode a [cookie-value](https://datatracker.ietf.org/doc/html/rfc6265#section-4.1.1). Defaults to [`encodeURIComponent`](#encode-and-decode).
### cookie.parseSetCookie(str, options)
Parse an HTTP `Set-Cookie` header string and return an [object](#set-cookie-object) of the options.
```js
const setCookieObject = cookie.parseSetCookie("foo=bar; httpOnly");
// { name: "foo", value: "bar", httpOnly: true }
```
**Note:** Cookie follows the specification and ignores invalid attributes, but does not attempt to normalize or modify any attributes as a browser might. For example:
```js
cookie.parseSetCookie(
"session=abc; max-age=1.5; expires=invalid; custom=value; domain=example.com",
);
// { name: "session", value: "abc", domain: "example.com" }
```
#### Options
- `decode` Specifies the function to decode a [cookie-value](https://datatracker.ietf.org/doc/html/rfc6265#section-4.1.1). Defaults to [`decodeURIComponent`](#encode-and-decode).
### cookie.stringifySetCookie(setCookieObj, options)
Stringifies a [`Set-Cookie` object](#set-cookie-object) into a `Set-Cookie` header string.
```js
const setCookieHeader = cookie.stringifySetCookie({
name: "foo",
value: "bar",
});
// foo=bar
```
#### Options
- `encode` Specifies the function to encode a [cookie-value](https://datatracker.ietf.org/doc/html/rfc6265#section-4.1.1). Defaults to [`encodeURIComponent`](#encode-and-decode).
## Cookie object
The cookie object represents all cookie name-value pairs in a `Cookie` header, where `{ name: "value" }` is used for `name=value`.
## `Set-Cookie` object
The `Set-Cookie` object represents all the options in a `Set-Cookie` header.
### name
The name of the cookie.
### value
The value of a cookie after it has been [decoded](#encode-and-decode).
### maxAge
Specifies the `number` (in seconds) to be the value for the [`Max-Age` `Set-Cookie` attribute](https://tools.ietf.org/html/rfc6265#section-5.2.2).
The [cookie storage model specification](https://tools.ietf.org/html/rfc6265#section-5.3) states that if both `expires` and
`maxAge` are set, then `maxAge` takes precedence, but it is possible not all clients by obey this,
so if both are set, they should point to the same date and time.
### expires
Specifies the `Date` object to be the value for the [`Expires` `Set-Cookie` attribute](https://tools.ietf.org/html/rfc6265#section-5.2.1).
When no expiration is set, clients consider this a "non-persistent cookie" and delete it when the current session is over.
The [cookie storage model specification](https://tools.ietf.org/html/rfc6265#section-5.3) states that if both `expires` and
`maxAge` are set, then `maxAge` takes precedence, but it is possible not all clients by obey this,
so if both are set, they should point to the same date and time.
### domain
Specifies the value for the [`Domain` `Set-Cookie` attribute](https://tools.ietf.org/html/rfc6265#section-5.2.3).
When no domain is set, clients consider the cookie to apply to the current domain only.
### path
Specifies the value for the [`Path` `Set-Cookie` attribute](https://tools.ietf.org/html/rfc6265#section-5.2.4).
When no path is set, the path is considered the ["default path"](https://tools.ietf.org/html/rfc6265#section-5.1.4).
### httpOnly
Enables the [`HttpOnly` `Set-Cookie` attribute](https://tools.ietf.org/html/rfc6265#section-5.2.6).
When enabled, clients will not allow client-side JavaScript to see the cookie in `document.cookie`.
### secure
Enables the [`Secure` `Set-Cookie` attribute](https://tools.ietf.org/html/rfc6265#section-5.2.5).
When enabled, clients will only send the cookie back if the browser has an HTTPS connection.
### partitioned
Enables the [`Partitioned` `Set-Cookie` attribute](https://tools.ietf.org/html/draft-cutler-httpbis-partitioned-cookies/).
When enabled, clients will only send the cookie back when the current domain _and_ top-level domain matches.
This is an attribute that has not yet been fully standardized, and may change in the future.
This also means clients may ignore this attribute until they understand it. More information
about can be found in [the proposal](https://github.com/privacycg/CHIPS).
### priority
Specifies the value for the [`Priority` `Set-Cookie` attribute](https://tools.ietf.org/html/draft-west-cookie-priority-00#section-4.1).
- `'low'` will set the `Priority` attribute to `Low`.
- `'medium'` will set the `Priority` attribute to `Medium`, the default priority when not set.
- `'high'` will set the `Priority` attribute to `High`.
More information about priority levels can be found in [the specification](https://tools.ietf.org/html/draft-west-cookie-priority-00#section-4.1).
### sameSite
Specifies the value for the [`SameSite` `Set-Cookie` attribute](https://tools.ietf.org/html/draft-ietf-httpbis-rfc6265bis-09#section-5.4.7).
- `true` will set the `SameSite` attribute to `Strict` for strict same site enforcement.
- `'lax'` will set the `SameSite` attribute to `Lax` for lax same site enforcement.
- `'none'` will set the `SameSite` attribute to `None` for an explicit cross-site cookie.
- `'strict'` will set the `SameSite` attribute to `Strict` for strict same site enforcement.
More information about enforcement levels can be found in [the specification](https://tools.ietf.org/html/draft-ietf-httpbis-rfc6265bis-09#section-5.4.7).
## Encode and decode
Cookie accepts `encode` or `decode` options for processing a [cookie-value](https://datatracker.ietf.org/doc/html/rfc6265#section-4.1.1).
Since the value of a cookie has a limited character set (and must be a simple string), these functions are used to transform values into strings suitable for a cookies value.
The default `encode` function is the global `encodeURIComponent`.
The default `decode` function is the global `decodeURIComponent`, wrapped in a `try..catch`. If an error
is thrown it will return the cookie's original value. If you provide your own encode/decode
scheme you must ensure errors are appropriately handled.
## Example
The following example uses this module in conjunction with the Node.js core HTTP server
to prompt a user for their name and display it back on future visits.
```js
var cookie = require("cookie");
var escapeHtml = require("escape-html");
var http = require("http");
var url = require("url");
function onRequest(req, res) {
// Parse the query string
var query = url.parse(req.url, true, true).query;
if (query && query.name) {
// Set a new cookie with the name
res.setHeader(
"Set-Cookie",
cookie.stringifySetCookie({
name: "name",
value: String(query.name),
httpOnly: true,
maxAge: 60 * 60 * 24 * 7, // 1 week
}),
);
// Redirect back after setting cookie
res.statusCode = 302;
res.setHeader("Location", req.headers.referer || "/");
res.end();
return;
}
// Parse the cookies on the request
var cookies = cookie.parseCookie(req.headers.cookie || "");
// Get the visitor name set in the cookie
var name = cookies.name;
res.setHeader("Content-Type", "text/html; charset=UTF-8");
if (name) {
res.write("Welcome back, " + escapeHtml(name) + "!
");
} else {
res.write("Hello, new visitor!
");
}
res.write('");
}
http.createServer(onRequest).listen(3000);
```
## Testing
```sh
npm test
```
## Benchmark
```sh
npm run bench
```
```
name hz min max mean p75 p99 p995 p999 rme samples
· simple 8,566,313.09 0.0000 0.3694 0.0001 0.0001 0.0002 0.0002 0.0003 ±0.64% 4283157 fastest
· decode 3,834,348.85 0.0001 0.2465 0.0003 0.0003 0.0003 0.0004 0.0006 ±0.38% 1917175
· unquote 8,315,355.96 0.0000 0.3824 0.0001 0.0001 0.0002 0.0002 0.0003 ±0.72% 4157880
· duplicates 1,944,765.97 0.0004 0.2959 0.0005 0.0005 0.0006 0.0006 0.0008 ±0.24% 972384
· 10 cookies 675,345.67 0.0012 0.4328 0.0015 0.0015 0.0019 0.0020 0.0058 ±0.75% 337673
· 100 cookies 61,040.71 0.0152 0.4092 0.0164 0.0160 0.0196 0.0228 0.2260 ±0.71% 30521 slowest
✓ parse top-sites (15) 22945ms
name hz min max mean p75 p99 p995 p999 rme samples
· parse accounts.google.com 7,164,349.17 0.0000 0.0929 0.0001 0.0002 0.0002 0.0002 0.0003 ±0.09% 3582184
· parse apple.com 7,817,686.84 0.0000 0.6048 0.0001 0.0001 0.0002 0.0002 0.0003 ±1.05% 3908844
· parse cloudflare.com 7,189,841.70 0.0000 0.0390 0.0001 0.0002 0.0002 0.0002 0.0003 ±0.06% 3594921
· parse docs.google.com 7,051,765.61 0.0000 0.0296 0.0001 0.0002 0.0002 0.0002 0.0003 ±0.06% 3525883
· parse drive.google.com 7,349,104.77 0.0000 0.0368 0.0001 0.0001 0.0002 0.0002 0.0003 ±0.05% 3674553
· parse en.wikipedia.org 1,929,909.49 0.0004 0.3598 0.0005 0.0005 0.0007 0.0007 0.0012 ±0.16% 964955
· parse linkedin.com 2,225,658.01 0.0003 0.0595 0.0004 0.0005 0.0005 0.0005 0.0006 ±0.06% 1112830
· parse maps.google.com 4,423,511.68 0.0001 0.0942 0.0002 0.0003 0.0003 0.0003 0.0005 ±0.08% 2211756
· parse microsoft.com 3,387,601.88 0.0002 0.0725 0.0003 0.0003 0.0004 0.0004 0.0005 ±0.09% 1693801
· parse play.google.com 7,375,980.86 0.0000 0.1994 0.0001 0.0001 0.0002 0.0002 0.0003 ±0.12% 3687991
· parse support.google.com 4,912,267.94 0.0001 2.8958 0.0002 0.0002 0.0003 0.0003 0.0005 ±1.28% 2456134
· parse www.google.com 3,443,035.87 0.0002 0.2783 0.0003 0.0003 0.0004 0.0004 0.0007 ±0.51% 1721518
· parse youtu.be 1,910,492.87 0.0004 0.3490 0.0005 0.0005 0.0007 0.0007 0.0011 ±0.46% 955247
· parse youtube.com 1,895,082.62 0.0004 0.7454 0.0005 0.0005 0.0006 0.0007 0.0013 ±0.64% 947542 slowest
· parse example.com 21,582,835.27 0.0000 0.1095 0.0000 0.0000 0.0001 0.0001 0.0001 ±0.13% 10791418
```
## References
- [RFC 6265: HTTP State Management Mechanism](https://tools.ietf.org/html/rfc6265)
- [Same-site Cookies](https://tools.ietf.org/html/draft-ietf-httpbis-rfc6265bis-09#section-5.4.7)
## License
[MIT](LICENSE)
[ci-image]: https://img.shields.io/github/actions/workflow/status/jshttp/cookie/ci.yml
[ci-url]: https://github.com/jshttp/cookie/actions/workflows/ci.yml?query=branch%3Amaster
[coverage-image]: https://img.shields.io/codecov/c/github/jshttp/cookie/master
[coverage-url]: https://app.codecov.io/gh/jshttp/cookie
[npm-downloads-image]: https://img.shields.io/npm/dm/cookie
[npm-url]: https://npmjs.org/package/cookie
[npm-version-image]: https://img.shields.io/npm/v/cookie