src/Routes/Route.php
protected function processResponse($response) {
        if ($response instanceof ResponseInterface) {
            return $response;
        }
        if ($response instanceof ResponseBuilderInterface) {
            return $response->build();
        }
        //Do not throw error on console app
        if (Reaction::isConsoleApp()) {
            return $response;
        }
        $type = is_object($response) ? get_class($response) : gettype($response);
        $message = sprintf('Return value must be instance of "%s", but "%s" given', ResponseInterface::class, $type);
        throw new InvalidArgumentException($message);
    }
protected function processResponse($response) {
        if ($response instanceof ResponseInterface) {
            return $response;
        }
        if ($response instanceof ResponseBuilderInterface) {
            return $response->build();
        }
        //Do not throw error on console app
        if (Reaction::isConsoleApp()) {
            return $response;
        }
        $type = is_object($response) ? get_class($response) : gettype($response);
        $message = sprintf('Return value must be instance of "%s", but "%s" given', ResponseInterface::class, $type);
        throw new InvalidArgumentException($message);
    }
Process response from controller action
@param ResponseInterface|ResponseBuilderInterface $response
@return ResponseInterface