js-cookie/js-cookie

View on GitHub
README.md

Summary

Maintainability
Test Coverage
<p align="center">
  <img src="https://cloud.githubusercontent.com/assets/835857/14581711/ba623018-0436-11e6-8fce-d2ccd4d379c9.gif">
</p>

# JavaScript Cookie [![CI](https://github.com/js-cookie/js-cookie/actions/workflows/ci.yml/badge.svg)](https://github.com/js-cookie/js-cookie/actions/workflows/ci.yml) [![Code Climate](https://codeclimate.com/github/js-cookie/js-cookie.svg)](https://codeclimate.com/github/js-cookie/js-cookie) [![npm](https://img.shields.io/github/package-json/v/js-cookie/js-cookie)](https://www.npmjs.com/package/js-cookie) [![size](https://img.shields.io/bundlephobia/minzip/js-cookie/3)](https://www.npmjs.com/package/js-cookie) [![jsDelivr Hits](https://data.jsdelivr.com/v1/package/npm/js-cookie/badge?style=rounded)](https://www.jsdelivr.com/package/npm/js-cookie)

A simple, lightweight JavaScript API for handling cookies

- Extensive browser support
- Accepts [any](#encoding) character
- [Heavily](test) tested
- No dependency
- Supports ES modules
- Supports AMD/CommonJS
- [RFC 6265](https://tools.ietf.org/html/rfc6265) compliant
- Useful [Wiki](https://github.com/js-cookie/js-cookie/wiki)
- Enable [custom encoding/decoding](#converters)
- **< 800 bytes** gzipped!

**πŸ‘‰πŸ‘‰ If you're viewing this at https://github.com/js-cookie/js-cookie, you're reading the documentation for the main branch.
[View documentation for the latest release.](https://github.com/js-cookie/js-cookie/tree/latest#readme) πŸ‘ˆπŸ‘ˆ**

## Installation

### NPM

JavaScript Cookie supports [npm](https://www.npmjs.com/package/js-cookie) under the name `js-cookie`.

```bash
npm i js-cookie
```

The npm package has a `module` field pointing to an ES module variant of the library, mainly to provide support for ES module aware bundlers, whereas its `browser` field points to an UMD module for full backward compatibility.

_Not all browsers support ES modules natively yet_. For this reason the npm package/release provides both the ES and UMD module variant and you may want to include the ES module along with the UMD fallback to account for this:

### CDN

Alternatively, include js-cookie via [jsDelivr CDN](https://www.jsdelivr.com/package/npm/js-cookie).

## Basic Usage

Import the library:

```javascript
import Cookies from 'js-cookie'
// or
const Cookies = require('js-cookie')
```

Create a cookie, valid across the entire site:

```javascript
Cookies.set('name', 'value')
```

Create a cookie that expires 7 days from now, valid across the entire site:

```javascript
Cookies.set('name', 'value', { expires: 7 })
```

Create an expiring cookie, valid to the path of the current page:

```javascript
Cookies.set('name', 'value', { expires: 7, path: '' })
```

Read cookie:

```javascript
Cookies.get('name') // => 'value'
Cookies.get('nothing') // => undefined
```

Read all visible cookies:

```javascript
Cookies.get() // => { name: 'value' }
```

_Note: It is not possible to read a particular cookie by passing one of the cookie attributes (which may or may not
have been used when writing the cookie in question):_

```javascript
Cookies.get('foo', { domain: 'sub.example.com' }) // `domain` won't have any effect...!
```

The cookie with the name `foo` will only be available on `.get()` if it's visible from where the
code is called; the domain and/or path attribute will not have an effect when reading.

Delete cookie:

```javascript
Cookies.remove('name')
```

Delete a cookie valid to the path of the current page:

```javascript
Cookies.set('name', 'value', { path: '' })
Cookies.remove('name') // fail!
Cookies.remove('name', { path: '' }) // removed!
```

_IMPORTANT! When deleting a cookie and you're not relying on the [default attributes](#cookie-attributes), you must pass the exact same `path`, `domain`, `secure` and `sameSite` attributes that were used to set the cookie:_

```javascript
Cookies.remove('name', { path: '', domain: '.yourdomain.com', secure: true })
```

_Note: Removing a nonexistent cookie neither raises any exception nor returns any value._

## Namespace conflicts

If there is any danger of a conflict with the namespace `Cookies`, the `noConflict` method will allow you to define a new namespace and preserve the original one. This is especially useful when running the script on third party sites e.g. as part of a widget or SDK.

```javascript
// Assign the js-cookie api to a different variable and restore the original "window.Cookies"
var Cookies2 = Cookies.noConflict()
Cookies2.set('name', 'value')
```

_Note: The `.noConflict` method is not necessary when using AMD or CommonJS, thus it is not exposed in those environments._

## Encoding

This project is [RFC 6265](http://tools.ietf.org/html/rfc6265#section-4.1.1) compliant. All special characters that are not allowed in the cookie-name or cookie-value are encoded with each one's UTF-8 Hex equivalent using [percent-encoding](http://en.wikipedia.org/wiki/Percent-encoding).
The only character in cookie-name or cookie-value that is allowed and still encoded is the percent `%` character, it is escaped in order to interpret percent input as literal.
Please note that the default encoding/decoding strategy is meant to be interoperable [only between cookies that are read/written by js-cookie](https://github.com/js-cookie/js-cookie/pull/200#discussion_r63270778). To override the default encoding/decoding strategy you need to use a [converter](#converters).

_Note: According to [RFC 6265](https://tools.ietf.org/html/rfc6265#section-6.1), your cookies may get deleted if they are too big or there are too many cookies in the same domain, [more details here](https://github.com/js-cookie/js-cookie/wiki/Frequently-Asked-Questions#why-are-my-cookies-being-deleted)._

## Cookie Attributes

Cookie attribute defaults can be set globally by creating an instance of the api via `withAttributes()`, or individually for each call to `Cookies.set(...)` by passing a plain object as the last argument. Per-call attributes override the default attributes.

### expires

Define when the cookie will be removed. Value must be a [`Number`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number) which will be interpreted as days from time of creation or a [`Date`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date) instance. If omitted, the cookie becomes a session cookie.

To create a cookie that expires in less than a day, you can check the [FAQ on the Wiki](https://github.com/js-cookie/js-cookie/wiki/Frequently-Asked-Questions#expire-cookies-in-less-than-a-day).

**Default:** Cookie is removed when the user closes the browser.

**Examples:**

```javascript
Cookies.set('name', 'value', { expires: 365 })
Cookies.get('name') // => 'value'
Cookies.remove('name')
```

### path

A [`String`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String) indicating the path where the cookie is visible.

**Default:** `/`

**Examples:**

```javascript
Cookies.set('name', 'value', { path: '' })
Cookies.get('name') // => 'value'
Cookies.remove('name', { path: '' })
```

**Note regarding Internet Explorer:**

> Due to an obscure bug in the underlying WinINET InternetGetCookie implementation, IE’s document.cookie will not return a cookie if it was set with a path attribute containing a filename.

(From [Internet Explorer Cookie Internals (FAQ)](http://blogs.msdn.com/b/ieinternals/archive/2009/08/20/wininet-ie-cookie-internals-faq.aspx))

This means one cannot set a path using `window.location.pathname` in case such pathname contains a filename like so: `/check.html` (or at least, such cookie cannot be read correctly).

In fact, you should never allow untrusted input to set the cookie attributes or you might be exposed to a [XSS attack](https://github.com/js-cookie/js-cookie/issues/396).

### domain

A [`String`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String) indicating a valid domain where the cookie should be visible. The cookie will also be visible to all subdomains.

**Default:** Cookie is visible only to the domain or subdomain of the page where the cookie was created, except for Internet Explorer (see below).

**Examples:**

Assuming a cookie that is being created on `site.com`:

```javascript
Cookies.set('name', 'value', { domain: 'subdomain.site.com' })
Cookies.get('name') // => undefined (need to read at 'subdomain.site.com')
```

**Note regarding Internet Explorer default behavior:**

> Q3: If I don’t specify a DOMAIN attribute (for) a cookie, IE sends it to all nested subdomains anyway?
> A: Yes, a cookie set on example.com will be sent to sub2.sub1.example.com.
> Internet Explorer differs from other browsers in this regard.

(From [Internet Explorer Cookie Internals (FAQ)](http://blogs.msdn.com/b/ieinternals/archive/2009/08/20/wininet-ie-cookie-internals-faq.aspx))

This means that if you omit the `domain` attribute, it will be visible for a subdomain in IE.

### secure

Either `true` or `false`, indicating if the cookie transmission requires a secure protocol (https).

**Default:** No secure protocol requirement.

**Examples:**

```javascript
Cookies.set('name', 'value', { secure: true })
Cookies.get('name') // => 'value'
Cookies.remove('name')
```

### sameSite

A [`String`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String), allowing to control whether the browser is sending a cookie along with cross-site requests.

Default: not set.

**Note that more recent browsers are making "Lax" the default value even without specifiying anything here.**

**Examples:**

```javascript
Cookies.set('name', 'value', { sameSite: 'strict' })
Cookies.get('name') // => 'value'
Cookies.remove('name')
```

### Setting up defaults

```javascript
const api = Cookies.withAttributes({ path: '/', domain: '.example.com' })
```

## Converters

### Read

Create a new instance of the api that overrides the default decoding implementation. All get methods that rely in a proper decoding to work, such as `Cookies.get()` and `Cookies.get('name')`, will run the given converter for each cookie. The returned value will be used as the cookie value.

Example from reading one of the cookies that can only be decoded using the `escape` function:

```javascript
document.cookie = 'escaped=%u5317'
document.cookie = 'default=%E5%8C%97'
var cookies = Cookies.withConverter({
  read: function (value, name) {
    if (name === 'escaped') {
      return unescape(value)
    }
    // Fall back to default for all other cookies
    return Cookies.converter.read(value, name)
  }
})
cookies.get('escaped') // εŒ—
cookies.get('default') // εŒ—
cookies.get() // { escaped: 'εŒ—', default: 'εŒ—' }
```

### Write

Create a new instance of the api that overrides the default encoding implementation:

```javascript
Cookies.withConverter({
  write: function (value, name) {
    return value.toUpperCase()
  }
})
```

## TypeScript declarations

```bash
npm i @types/js-cookie
```

## Server-side integration

Check out the [Servers Docs](SERVER_SIDE.md)

## Contributing

Check out the [Contributing Guidelines](CONTRIBUTING.md)

## Releasing

Releasing should be done via the `Release` GitHub Actions workflow, so that published packages on npmjs.com have package provenance.

GitHub releases are created as a draft and need to be published manually!
(This is so we are able to craft suitable release notes before publishing.)

## Supporters

<p>
  <a href="https://www.browserstack.com/"><img src="https://raw.githubusercontent.com/wiki/js-cookie/js-cookie/Browserstack-logo%402x.png" width="150"></a>
</p>

Many thanks to [BrowserStack](https://www.browserstack.com/) for providing unlimited browser testing free of cost.

## Authors

- [Klaus Hartl](https://github.com/carhartl)
- [Fagner Brack](https://github.com/FagnerMartinsBrack)
- And awesome [contributors](https://github.com/js-cookie/js-cookie/graphs/contributors)