Avoid duplicate App container creation

Signed-off-by: Joas Schilling <coding@schilljs.com>

lib/private/ServerContainer.php

@@ -71,6 +71,19 @@ class ServerContainer extends SimpleContainer {
 		$this->appContainers[strtolower(App::buildAppNamespace($appName, ''))] = $container;
 	}
 
+	/**
+	 * @param string $appName
+	 * @return DIContainer
+	 * @throws QueryException
+	 */
+	public function getRegisteredAppContainer(string $appName) {
+		if (isset($this->appContainers[strtolower(App::buildAppNamespace($appName, ''))])) {
+			return $this->appContainers[strtolower(App::buildAppNamespace($appName, ''))];
+		}
+
+		throw new QueryException();
+	}
+
 	/**
 	 * @param string $namespace
 	 * @param string $sensitiveNamespace

lib/public/AppFramework/App.php

@@ -66,11 +66,16 @@ class App {
 
 
 	/**
+	 * @param string $appName
 	 * @param array $urlParams an array with variables extracted from the routes
 	 * @since 6.0.0
 	 */
 	public function __construct(string $appName, array $urlParams = []) {
-		$this->container = new \OC\AppFramework\DependencyInjection\DIContainer($appName, $urlParams);
+		try {
+			$this->container = \OC::$server->getRegisteredAppContainer($appName);
+		} catch (QueryException $e) {
+			$this->container = new \OC\AppFramework\DependencyInjection\DIContainer($appName, $urlParams);
+		}
 	}
 
 	/**