First commit of new examples

examples/client-credentials/index.php

@@ -0,0 +1,23 @@
+<?php
+
+use Symfony\Component\HttpFoundation\Request;
+
+include (__DIR__.'/../vendor/autoload.php');
+
+// Setup the authorization server
+$server = new \League\OAuth2\Server\Server();
+$server->addRepository(new \OAuth2ServerExamples\Repositories\ClientRepository());
+$server->addRepository(new \OAuth2ServerExamples\Repositories\ScopeRepository());
+$server->addRepository(new \OAuth2ServerExamples\Repositories\AccessTokenRepository());
+
+// Enable the client credentials grant which will return access tokens that last for 24 hours
+$server->enableGrantType('ClientCredentialsGrant', null, new \DateInterval('PT24H'));
+
+// Setup the routing
+$application = new \Proton\Application();
+$application->post('/access_token', function (Request $request) use ($server) {
+    return $server->getAccessTokenResponse($request);
+});
+
+// Run the app
+$application->run();