negotiator

An HTTP content negotiator for Node.js

# Installation

$ npm install negotiator

# API

var Negotiator = require('negotiator')

## Accept Negotiation

availableMediaTypes = ['text/html', 'text/plain', 'application/json']
// The negotiator constructor receives a request object
negotiator = new Negotiator(request)
// Let's say Accept header is 'text/html, application/*;q=0.2, image/jpeg;q=0.8'
negotiator.mediaTypes()
// -> ['text/html', 'image/jpeg', 'application/*']
negotiator.mediaTypes(availableMediaTypes)
// -> ['text/html', 'application/json']
negotiator.mediaType(availableMediaTypes)
// -> 'text/html'

You can check a working example at `examples/accept.js`.

### Methods

#### mediaType()

Returns the most preferred media type from the client.

#### mediaType(availableMediaType)

Returns the most preferred media type from a list of available media types.

#### mediaTypes()

Returns an array of preferred media types ordered by the client preference.

#### mediaTypes(availableMediaTypes)

Returns an array of preferred media types ordered by priority from a list of available media types.

## Accept-Language Negotiation

negotiator = new Negotiator(request)
availableLanguages = ['en', 'es', 'fr']
// Let's say Accept-Language header is 'en;q=0.8, es, pt'
negotiator.languages()
// -> ['es', 'pt', 'en']
negotiator.languages(availableLanguages)
// -> ['es', 'en']
language = negotiator.language(availableLanguages)
// -> 'es'

You can check a working example at `examples/language.js`.

### Methods

#### language()

Returns the most preferred language from the client.

#### language(availableLanguages)

Returns the most preferred language from a list of available languages.

#### languages()

Returns an array of preferred languages ordered by the client preference.

#### languages(availableLanguages)

Returns an array of preferred languages ordered by priority from a list of available languages.

## Accept-Charset Negotiation

availableCharsets = ['utf-8', 'iso-8859-1', 'iso-8859-5']
negotiator = new Negotiator(request)
// Let's say Accept-Charset header is 'utf-8, iso-8859-1;q=0.8, utf-7;q=0.2'
negotiator.charsets()
// -> ['utf-8', 'iso-8859-1', 'utf-7']
negotiator.charsets(availableCharsets)
// -> ['utf-8', 'iso-8859-1']
negotiator.charset(availableCharsets)
// -> 'utf-8'

You can check a working example at `examples/charset.js`.

### Methods

#### charset()

Returns the most preferred charset from the client.

#### charset(availableCharsets)

Returns the most preferred charset from a list of available charsets.

#### charsets()

Returns an array of preferred charsets ordered by the client preference.

#### charsets(availableCharsets)

Returns an array of preferred charsets ordered by priority from a list of available charsets.

## Accept-Encoding Negotiation

availableEncodings = ['identity', 'gzip']
negotiator = new Negotiator(request)
// Let's say Accept-Encoding header is 'gzip, compress;q=0.2, identity;q=0.5'
negotiator.encodings()
// -> ['gzip', 'identity', 'compress']
negotiator.encodings(availableEncodings)
// -> ['gzip', 'identity']
negotiator.encoding(availableEncodings)
// -> 'gzip'

You can check a working example at `examples/encoding.js`.

### Methods

#### encoding()

Returns the most preferred encoding from the client.

#### encoding(availableEncodings)

Returns the most preferred encoding from a list of available encodings.

#### encodings()

Returns an array of preferred encodings ordered by the client preference.

#### encodings(availableEncodings)

Returns an array of preferred encodings ordered by priority from a list of available encodings.

# See Also

The accepts module builds on this module and provides an alternative interface, mime type validation, and more.

# License

[MIT](LICENSE)