Client: require composer 2 and extract api client from InstalledVersions

Author: wissem

composer.json

@@ -16,7 +16,8 @@
         "php-http/httplug": "^1.1 || ^2.0",
         "php-http/discovery": "^1.0",
         "php-http/client-implementation": "^1.0",
-        "php-http/client-common": "^1.9 || ^2.0"
+        "php-http/client-common": "^1.9 || ^2.0",
+        "composer-runtime-api": "^2.0"
     },
     "require-dev": {
         "phpunit/phpunit": "^5.5 || ^7.0",

src/Client.php

@@ -19,8 +19,6 @@
 
 class Client
 {
-    const API_CLIENT_VERSION = '1.21.0';
-
     /** @var HttpPluginClientBuilder */
     private $httpClientBuilder;
     /** @var ResponseMediator */
@@ -31,15 +29,18 @@ public function __construct(HttpPluginClientBuilder $httpClientBuilder = null, $
     {
         $this->httpClientBuilder = $builder = $httpClientBuilder ?: new HttpPluginClientBuilder();
         $privatePackagistUrl = $privatePackagistUrl ? : 'https://packagist.com';
-        $this->responseMediator = $responseMediator ? $responseMediator : new ResponseMediator();
+        $this->responseMediator = $responseMediator ? : new ResponseMediator();
 
         $builder->addPlugin(new Plugin\AddHostPlugin(UriFactoryDiscovery::find()->createUri($privatePackagistUrl)));
         $builder->addPlugin(new PathPrepend('/api'));
         $builder->addPlugin(new Plugin\RedirectPlugin());
-        $builder->addPlugin(new Plugin\HeaderDefaultsPlugin([
+        $headers = [
             'User-Agent' => 'php-private-packagist-api (https://github.com/packagist/private-packagist-api-client)',
-            'X-API-CLIENT-VERSION' => self::API_CLIENT_VERSION,
-        ]));
+        ];
+        if ($apiClientVersion = $this->getApiClientVersion()) {
+            $headers['API-CLIENT-VERSION'] = $apiClientVersion;
+        }
+        $builder->addPlugin(new Plugin\HeaderDefaultsPlugin($headers));
         $builder->addPlugin(new ExceptionThrower($this->responseMediator));
     }
 
@@ -121,4 +122,17 @@ protected function getHttpClientBuilder()
     {
         return $this->httpClientBuilder;
     }
+
+    private function getApiClientVersion()
+    {
+        try {
+            if ($version = \Composer\InstalledVersions::getVersion('private-packagist/api-client')) {
+                return $version;
+            }
+        } catch (\OutOfBoundsException $exception) {
+            return null;
+        }
+
+        return null;
+    }
 }