Topics

Content Negociation

The [ContentNegociation](NoreSources\Http\ContentNegociation\ContentNegociator) class returns the preferred Content-* header values according the Accept-* header values of a HTTP request and the server supported content formats.

Request header → Response header
Accept Content-Type
Accept-Charser Content-Type `charset` parameter
Accept-Encoding Content-Encoding
Accept-Language Content-Language

Example

use NoreSources\Http\ContentNegociation\ContentNegociator;
use NoreSources\Http\Header\HeaderField;
use Psr\Http\Message\ServerRequestInterface;

// A router request controller
function handleRequest (ServerRequestInterface $request) 
{
	$supportedMediaTypes = [ 
		 /* List of media types */
		 'application/json',
		 'text/yaml',
		 'text/html'
	];
	$supportedLanguage = [
	 /* List of language tags */
	'fr-FR', 'en-UK', 'en-US'
	];
	$negociator = ContentNegociator::getInstance();
	$negociation = $negociator->negociate($request, [
				HeaderField::CONTENT_TYPE => 	$supportedMediaTypes,
				HeaderField::CONTENT_LANGUAGE => 	$supportedLanguage
	]);

	// Build content according result of negociation
	$content = getResponseContentFor ($negociation);

	// Build response with content and headers
	// returned by negociation
	$response = new TextResponse($content);
	foreach ($negociation as $header => $value)
		$response = $response->withHeader ($header, \strval($value));
	
	return $response;
}

References