What is the best pattern for abstract modules that can be injected multiple times?

[cep21]

Let's say I have an HTTP server module like this where the server takes an array of mux wrappers as a parameter.

var Module = fx.Module("httpserver", fx.Options(
	fx.Provide(
                fx.Annotate(
		  NewHTTPServer,
                  fx.ParamTags(`"group:"mux-wrappers"`),
         )
))

This module lives in an abstract "make an HTTP server" package. People can now use this module to make their own HTTP sever.

But what if they want to make two HTTP servers: one for regular requests and one to serve the :6060/debug/vars requests?

They could import the module twice, but then both modules are asking for the same ParamTags group named "mux-wrappers" and there's no way for users to say which server a mux wrapper belongs to.

One solution is to change var Module into a function

func Module(rootName string) fx.Option {
  return  fx.Module(rootName + "httpserver", fx.Options(
    fx.Provide(
      fx.Annotate(
        NewHTTPServer,
        fx.ParamTags(`"group:"` + rootName + `mux-wrappers"`),
      )
  ))
}

Then I guess I have helpers for creating the correct mux wrapper name for users? The downside here is that I need to know ahead of time people want to use a module multiple times.

Is it possible with decorators to do something like this?