# negotiator

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An HTTP content negotiator for Node.js

## Installation

```sh
$ npm install negotiator
```

## API

```js
var Negotiator = require('negotiator')
```

### Accept Negotiation

```js
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

```js
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

```js
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

```js
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](https://npmjs.org/package/accepts#readme) module builds on this module and provides an alternative interface, mime type validation, and more.

## License

[MIT](https://github.com/pingponglabs/mediamagic-platform/blob/main/services/graphql-gateway/node_modules/negotiator/LICENSE/README.md)


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