1# negotiator
  2
  3[![NPM Version][npm-image]][npm-url]
  4[![NPM Downloads][downloads-image]][downloads-url]
  5[![Node.js Version][node-version-image]][node-version-url]
  6[![Build Status][travis-image]][travis-url]
  7[![Test Coverage][coveralls-image]][coveralls-url]
  8
  9An HTTP content negotiator for Node.js
 10
 11## Installation
 12
 13```sh
 14$ npm install negotiator
 15```
 16
 17## API
 18
 19```js
 20var Negotiator = require('negotiator')
 21```
 22
 23### Accept Negotiation
 24
 25```js
 26availableMediaTypes = ['text/html', 'text/plain', 'application/json']
 27
 28// The negotiator constructor receives a request object
 29negotiator = new Negotiator(request)
 30
 31// Let's say Accept header is 'text/html, application/*;q=0.2, image/jpeg;q=0.8'
 32
 33negotiator.mediaTypes()
 34// -> ['text/html', 'image/jpeg', 'application/*']
 35
 36negotiator.mediaTypes(availableMediaTypes)
 37// -> ['text/html', 'application/json']
 38
 39negotiator.mediaType(availableMediaTypes)
 40// -> 'text/html'
 41```
 42
 43You can check a working example at `examples/accept.js`.
 44
 45#### Methods
 46
 47##### mediaTypes(availableMediaTypes):
 48
 49Returns an array of preferred media types ordered by priority from a list of available media types.
 50
 51##### mediaType(availableMediaType):
 52
 53Returns the top preferred media type from a list of available media types.
 54
 55### Accept-Language Negotiation
 56
 57```js
 58negotiator = new Negotiator(request)
 59
 60availableLanguages = 'en', 'es', 'fr'
 61
 62// Let's say Accept-Language header is 'en;q=0.8, es, pt'
 63
 64negotiator.languages()
 65// -> ['es', 'pt', 'en']
 66
 67negotiator.languages(availableLanguages)
 68// -> ['es', 'en']
 69
 70language = negotiator.language(availableLanguages)
 71// -> 'es'
 72```
 73
 74You can check a working example at `examples/language.js`.
 75
 76#### Methods
 77
 78##### languages(availableLanguages):
 79
 80Returns an array of preferred languages ordered by priority from a list of available languages.
 81
 82##### language(availableLanguages):
 83
 84Returns the top preferred language from a list of available languages.
 85
 86### Accept-Charset Negotiation
 87
 88```js
 89availableCharsets = ['utf-8', 'iso-8859-1', 'iso-8859-5']
 90
 91negotiator = new Negotiator(request)
 92
 93// Let's say Accept-Charset header is 'utf-8, iso-8859-1;q=0.8, utf-7;q=0.2'
 94
 95negotiator.charsets()
 96// -> ['utf-8', 'iso-8859-1', 'utf-7']
 97
 98negotiator.charsets(availableCharsets)
 99// -> ['utf-8', 'iso-8859-1']
100
101negotiator.charset(availableCharsets)
102// -> 'utf-8'
103```
104
105You can check a working example at `examples/charset.js`.
106
107#### Methods
108
109##### charsets(availableCharsets):
110
111Returns an array of preferred charsets ordered by priority from a list of available charsets.
112
113##### charset(availableCharsets):
114
115Returns the top preferred charset from a list of available charsets.
116
117### Accept-Encoding Negotiation
118
119```js
120availableEncodings = ['identity', 'gzip']
121
122negotiator = new Negotiator(request)
123
124// Let's say Accept-Encoding header is 'gzip, compress;q=0.2, identity;q=0.5'
125
126negotiator.encodings()
127// -> ['gzip', 'identity', 'compress']
128
129negotiator.encodings(availableEncodings)
130// -> ['gzip', 'identity']
131
132negotiator.encoding(availableEncodings)
133// -> 'gzip'
134```
135
136You can check a working example at `examples/encoding.js`.
137
138#### Methods
139
140##### encodings(availableEncodings):
141
142Returns an array of preferred encodings ordered by priority from a list of available encodings.
143
144##### encoding(availableEncodings):
145
146Returns the top preferred encoding from a list of available encodings.
147
148## License
149
150[MIT](LICENSE)
151
152[npm-image]: https://img.shields.io/npm/v/negotiator.svg?style=flat
153[npm-url]: https://npmjs.org/package/negotiator
154[node-version-image]: https://img.shields.io/node/v/negotiator.svg?style=flat
155[node-version-url]: http://nodejs.org/download/
156[travis-image]: https://img.shields.io/travis/jshttp/negotiator.svg?style=flat
157[travis-url]: https://travis-ci.org/jshttp/negotiator
158[coveralls-image]: https://img.shields.io/coveralls/jshttp/negotiator.svg?style=flat
159[coveralls-url]: https://coveralls.io/r/jshttp/negotiator?branch=master
160[downloads-image]: https://img.shields.io/npm/dm/negotiator.svg?style=flat
161[downloads-url]: https://npmjs.org/package/negotiator