Resolves the response's current language based on the requested URI, the client's preferred language, and the available languages.

Alters the ResponseInterface to assign the Content-Language header.

Uses willdurand/Negotiation to detect and negotiate the client language.

Via Composer:

composer require mcaskill/slim-polyglot

Requires Slim 3.

use Slim\App;
use McAskill\Slim\Polyglot\Polyglot;

$app = new App();

// Fetch DI Container
$container = $app->getContainer();

// Register Middleware
$app->add(new Polyglot([ 'en', 'fr', 'es' ]));

// Example route with ETag header
$app->get('/foo', function ($request, $response) {
	$language = $response->getHeader('Content-Language');

	// Handle response!
});

$app->run();

The Polyglot middleware can also accept callbacks that are executed after a language is chosen.

use Slim\App;
use McAskill\Slim\Polyglot\Polyglot;

$app = new App();

// Fetch DI Container
$container = $app->getContainer();

// Register Middleware
$app->add(
	new Polyglot([
		'languages' => [ 'en', 'fr', 'es' ],
		'fallbackLanguage' => 'fr',
		// Hooks to call after language is resolved
		'callbacks' => [
			function ($language) use ($container) {
				$container['environment']['language.current'] = $language;
			},
			[ 'MySuperApp', 'set_language' ]
		]
	])
);

// Example route with ETag header
$app->get('/foo', function ($request, $response) {
	$language = $this->environment['language.current'];

	// Handle response!
});

$app->run();

TBD

The language code may be formatted as ISO 639-1 alpha-2 (en), ISO 639-3 alpha-3 (msa), or ISO 639-1 alpha-2 combined with an ISO 3166-1 alpha-2 localization (zh-tw).

[ "en", "fr-CA" ]

When giving a list of languages to the Polyglot middleware, the first language is used as the fallback language. When switching to a language that is not in the list of supported languages, the first language is used instead.

Definitions:

• "language-fallback" — Default language; determined as the first among your supported languages.
• "language-preferred" — Preferred language(s); determined as the client's localization preferences.
• "language-current" — Current language; determined as the localization to use based on a cross-reference of the application's supported languages and the client's priority of preferred languages.

The MIT License (MIT). Please see the License File for more information.