3.3.1. Controller location

In the standard Merb application layout, all web controllers are located within the directory app/controllers/. We say all web controllers because the other controllers, MailController and PartController, tend to live elsewhere in other directories. However, if you’re using the flat layout, you’ll find that all of your controllers are kept in one file, application.rb. Also, in the case of the very flat layout, your controllers basically have nowhere else to live but as part of a single file. Note that both the flat and very flat layouts are generated with a custom controller subclassed directly from Merb::Controller instead of Application. This seems to be based on the assumption that you’ll be making an application small enough that it does not need a parent class for all controllers. However, don’t let that restrict you—if you’re using the flatter layouts and need Application or Exception, by all means, code them in.

Even though it’s extremely rare to see someone deviate from the default locations, you can change the location of your controllers if you want. To do this, you can define a framework hash for Merb::Config inside the file config/framework.rb. This alters the default framework locations at Merb boot-up, but make sure you mention all locations you want to be set, because framework.rb doesn’t merge with the default settings. The following snippet shows, among other things, how to set the location of controllers to controllers/ as opposed to app/controllers: