# Plugin Separation/Integration using method\_missing **URL:** \ **Category:** Ruby\ **Created:** [September 28, 2007, 6:44am UTC](https://www.ruby-forum.com/t/plugin-separation-integration-using-method-missing/115751 "2007-09-28T06:44:37Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![daaku](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/9e8a1a/32.png) [@daaku](https://www.ruby-forum.com/u/daaku)\ **Post date:** [September 28, 2007, 6:44am UTC](https://www.ruby-forum.com/t/plugin-separation-integration-using-method-missing/115751/1 "2007-09-28T06:44:37Z")
I’m trying to implement a framework where I have a concept of ‘plugin overlays’. They plug into an application which provides a well defined external interface. The core of the plugin is a ‘service’ method that potentially alters the applications state. What I’m trying to achieve is to have the plugin run on ‘top-of’ the application. Essentially, forward all unknown messages to the Application as a fall-back (and fail there if needed). I have some code attached which forms the basis of my current implementation. Essentially use method\_missing and forward messages to the application. As I understand, assignment to what looks can be a local variable in a method will never go to method\_missing, but instead create a local variable. Alternatives for my case would be to explicitly create mappings for these methods before hand, or explicitly call a method on self. Is this a bad idea? My goal is to cleanly separate out code into reusable ‘plugins’ that still have full access to the application. Also, plugins must be isolated from each other. I know explicitly referring to the application instead of having things ‘fall-through’ is an option. Conceptually I’m thinking of this as a scope chain of sorts. On access to an variable or a method call, we look for it in the Plugin (and all its parents), and then the Application (and all its parents). -Naitik