chubbyts-negotiation

Description

A simple negotiation library.

Requirements

• node: 22
• @chubbyts/chubbyts-dic-config-factory: ^1.0.0
• @chubbyts/chubbyts-dic-types: ^2.3.0

Installation

Through NPM as @chubbyts/chubbyts-negotiation.

npm i @chubbyts/chubbyts-negotiation@^4.5.1

Usage

Accept-Language

import { createAcceptLanguageNegotiator } from '@chubbyts/chubbyts-negotiation/dist/accept-language-negotiator';

const negotiator = createAcceptLanguageNegotiator(['en', 'de']);
const value = negotiator.negotiate('de,en;q=0.3,en-US;q=0.7');

Accept

import { createAcceptNegotiator } from '@chubbyts/chubbyts-negotiation/dist/accept-negotiator';

const negotiator = createAcceptNegotiator(['application/json', 'application/xml', 'application/x-yaml']);
const value = negotiator.negotiate('text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q =0.8');

Content-Type

import { createContentTypeNegotiator } from '@chubbyts/chubbyts-negotiation/dist/content-type-negotiator';

const negotiator = createContentTypeNegotiator(['application/json', 'application/xml', 'application/x-yaml']);
const value = negotiator.negotiate('application/xml; charset=UTF-8');

Service factories (chubbyts-dic-config)

The package ships service factories (abstract factories built on chubbyts-dic-config-factory) for a chubbyts-dic-config (or any chubbyts-dic-types compatible) container within @chubbyts/chubbyts-negotiation/dist/service-factory.

Each negotiator reads its supported values from a <negotiator>SupportedValues service if registered, and falls back to a default otherwise:

• acceptLanguageNegotiatorServiceFactory: acceptLanguageNegotiatorSupportedValues, default []
• acceptNegotiatorServiceFactory: acceptNegotiatorSupportedValues, default the contentTypes of the encoder service
• contentTypeNegotiatorServiceFactory: contentTypeNegotiatorSupportedValues, default the contentTypes of the decoder service

The defaults are designed to reuse the type decoders / encoders of chubbyts-decode-encode (or anything else shaped like { contentTypes: Array<string> }), so the negotiators support exactly what can be decoded / encoded:

import type { ConfigFactory } from '@chubbyts/chubbyts-dic-config/dist/dic-config';
import { createContainerByConfigFactory } from '@chubbyts/chubbyts-dic-config/dist/dic-config';
import { decoderServiceFactory, encoderServiceFactory } from '@chubbyts/chubbyts-decode-encode/dist/service-factory';
import type { Negotiator } from '@chubbyts/chubbyts-negotiation/dist/negotiation';
import {
  acceptLanguageNegotiatorServiceFactory,
  acceptNegotiatorServiceFactory,
  contentTypeNegotiatorServiceFactory,
} from '@chubbyts/chubbyts-negotiation/dist/service-factory';

const container = createContainerByConfigFactory({
  dependencies: {
    factories: new Map<string, ConfigFactory>([
      ['decoder', decoderServiceFactory()],
      ['encoder', encoderServiceFactory()],
      ['acceptLanguageNegotiator', acceptLanguageNegotiatorServiceFactory()],
      ['acceptLanguageNegotiatorSupportedValues', (): Array<string> => ['en', 'de']],
      ['acceptNegotiator', acceptNegotiatorServiceFactory()],
      ['contentTypeNegotiator', contentTypeNegotiatorServiceFactory()],
    ]),
  },
})();

const acceptLanguageNegotiator = container.get<Negotiator>('acceptLanguageNegotiator'); // en, de
const acceptNegotiator = container.get<Negotiator>('acceptNegotiator'); // all encoder content types
const contentTypeNegotiator = container.get<Negotiator>('contentTypeNegotiator'); // all decoder content types

To override the supported values, register the related service:

const container = createContainerByConfigFactory({
  dependencies: {
    factories: new Map<string, ConfigFactory>([
      ['acceptNegotiator', acceptNegotiatorServiceFactory()],
      ['acceptNegotiatorSupportedValues', (): Array<string> => ['application/json']],
    ]),
  },
})();

With names

To negotiate different parts of an application with different supported values, the same factories can be registered multiple times with a name, which gets appended to each service id (acceptNegotiatorapi, acceptNegotiatorSupportedValuesapi, encoderapi, ...).

const container = createContainerByConfigFactory({
  dependencies: {
    factories: new Map<string, ConfigFactory>([
      ['decoderapi', decoderServiceFactory('api')],
      ['encoderapi', encoderServiceFactory('api')],
      ['acceptNegotiatorapi', acceptNegotiatorServiceFactory('api')],
      ['contentTypeNegotiatorapi', contentTypeNegotiatorServiceFactory('api')],
      ['acceptNegotiatoradmin', acceptNegotiatorServiceFactory('admin')],
      ['acceptNegotiatorSupportedValuesadmin', (): Array<string> => ['text/html']],
    ]),
  },
})();

const apiAcceptNegotiator = container.get<Negotiator>('acceptNegotiatorapi'); // content types of encoderapi
const adminAcceptNegotiator = container.get<Negotiator>('acceptNegotiatoradmin'); // text/html

Copyright

2026 Dominik Zogg