Content Negotiation tools for PHP.

This project is maintained by willdurand


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Negotiation is a standalone library without any dependencies that allows you to implement content negotiation in your application, whatever framework you use. This library is based on RFC 2616. Negotiation is easy to use, and extensively unit tested.


The recommended way to install Negotiation is through Composer:

    "require": {
        "willdurand/negotiation": "@stable"

Protip: you should browse the willdurand/negotiation page to choose a stable version to use, avoid the @stable meta constraint.


In a nutshell:


$negotiator = new \Negotiation\Negotiator();
$bestHeader = $negotiator->getBest('en; q=0.1, fr; q=0.4, fu; q=0.9, de; q=0.2');
// $bestHeader = 'fu';

The getBest() method, part of the NegotiatorInterface, returns either null or AcceptHeader instances. An AcceptHeader object owns a value and a quality.

Format Negotiation

The Format Negotiation is handled by the FormatNegotiator class. Basically, pass an Accept header and optionally a set of preferred media types to the getBest() method in order to retrieve the best media type:


$negotiator   = new \Negotiation\FormatNegotiator();

$acceptHeader = 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8';
$priorities   = array('text/html', 'application/json', '*/*');

$format = $negotiator->getBest($acceptHeader, $priorities);
// $format->getValue() = text/html

The FormatNegotiator class also provides a getBestFormat() method that returns the best format given an Accept header string and a set of preferred/allowed formats or mime types:


$negotiator   = new \Negotiation\FormatNegotiator();

$acceptHeader = 'text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8';
$priorities   = array('html', 'application/json', '*/*');

$format = $negotiator->getBestFormat($acceptHeader, $priorities);
// $format = html

Other Methods

Language Negotiation

Language negotiation is handled by the LanguageNegotiator class:


$negotiator = new \Negotiation\LanguageNegotiator();
$language   = $negotiator->getBest('da, en-gb;q=0.8, en;q=0.7');
// $language = da

Charset/Encoding Negotiation

Charset/Encoding negotiation works out of the box using the Negotiator class:


$negotiator = new \Negotiation\Negotiator();
$priorities = array(

$bestHeader = $negotiator->getBest('ISO-8859-1, Big5;q=0.6,utf-8;q=0.7, *;q=0.5', $priorities);
// $bestHeader = 'utf-8'

Unit Tests

Setup the test suite using Composer:

$ composer install --dev

Run it using PHPUnit:

$ phpunit





Negotiation is released under the MIT License. See the bundled LICENSE file for details.