Backport #415

src/Queue/ServicesTrait.php

@@ -4,23 +4,32 @@
 namespace Queue\Queue;
 
 use Cake\Core\ContainerInterface;
+use LogicException;
 
 trait ServicesTrait {
 
 	/**
-	 * @var \Cake\Core\ContainerInterface
+	 * @var \Cake\Core\ContainerInterface|null
 	 */
-	protected ContainerInterface $container;
+	protected ?ContainerInterface $container = null;
 
 	/**
-	 * @param string $id Classname or identifier of the service you want to retrieve
+	 * @template T
+	 *
+	 * @param class-string<T> $id Classname or identifier of the service you want to retrieve
 	 *
-	 * @throws \Psr\Container\NotFoundExceptionInterface
 	 * @throws \Psr\Container\ContainerExceptionInterface
+	 * @throws \Psr\Container\NotFoundExceptionInterface
 	 *
-	 * @return mixed
+	 * @return T
 	 */
-	protected function getService(string $id): mixed {
+	protected function getService(string $id) {
+		if ($this->container === null) {
+			throw new LogicException(
+				"The Container has not been set. Hint: getService() must not be called in the Task's constructor.",
+			);
+		}
+
 		return $this->container->get($id);
 	}