public function schemaListPOST(Request $request, Response $response, $args)
 {
     $this->logger->info(__CLASS__ . '::' . __FUNCTION__);
     $parsed = $request->getParsedBody();
     $fetch_me = $parsed['fetch_me'];
     $this->logger->info(__CLASS__ . '::' . __FUNCTION__ . ': fetch_me: ' . $fetch_me);
     $service = new SchemaService();
     $this->logger->info(__CLASS__ . '::' . __FUNCTION__ . ': have SchemaService instance.');
     $schemas = [];
     if ($fetch_me == 'all') {
         $this->logger->info(__CLASS__ . '::' . __FUNCTION__ . ': fetch all');
         $schemas = $service->schemas();
     } else {
         $this->logger->debug(__CLASS__ . '::' . __FUNCTION__ . ': $fetch_me: (mimeType): ' . $fetch_me);
         $schemas[$fetch_me] = $service->schema($fetch_me);
     }
     $this->logger->debug(__CLASS__ . '::' . __FUNCTION__ . ': count($schemas): ' . count($schemas));
     $text = serialize($schemas);
     return $response->getBody()->write($text);
 }