Function actix_service::factory_fn_cfg

pub fn factory_fn_cfg<F, Fut, Cfg, Srv, Err>(
    f: F
) -> FnServiceConfig<F, Fut, Cfg, Srv, Err> where
    F: Fn(Cfg) -> Fut,
    Fut: Future<Output = Result<Srv, Err>>,
    Srv: Service, 

Create ServiceFactory for function that can produce services with configuration