gistfile1.php

<?php

    public function createAction($threadIdentifier)
    {
        $thread = $this->container->get('fos_comment.manager.thread')->findThreadByIdentifier($threadIdentifier);
        if (!$thread) {
            throw new NotFoundHttpException(sprintf('Thread with identifier of "%s" does not exist', $threadIdentifier));
        }

        if ($replyToId = $this->container->get('request')->request->get('reply_to')) {
            $parent = $this->container->get('fos_comment.manager.comment')->findCommentById($replyToId);
            if (!$parent) {
                throw new NotFoundHttpException(sprintf('Parent comment with identifier "%s" does not exist', $replyToId));
            }
        } else {
            $parent = null;
        }

        $comment = $this->container->get('fos_comment.manager.comment')->createComment($thread, $replyTo);

        $form = $this->container->get('fos_comment.form_factory.comment')->createForm();
        $form->setData($comment);

        $request = $this->container->get('request');
        if ('POST' == $request->getMethod()) {
            $form->bindRequest($request);

            if ($form->isValid() && $this->container->get('fos_comment.creator.comment')->create($comment, $parent)) {
                return $this->onCreateSuccess($form);
            }
        }

        return $this->onCreateError($form);
    }