IoC container configuration

Question

How should the configuration for an IoC container be organized? I know that registering by code should be placed at the highest level in an application, but what if an application had hundreds of dependencies that need to be registered? Same with XML configurations. I know that you can split up the XML configurations into multiple files, but that would seem like it would become a maintenance hassle if someone had to dig through multiple XML files.

Are there any best practices for organizing the registration of dependencies? From all the videos and tutorials that I've seen, the code used in the demo were simple enough to place in a single location. I have yet to come across a sample application that utilizes a large number of dependencies.

Answer 1

It would help a little if we knew if you were talking about any particular IoC Container.

Windsor, for example, allows you to define dependencies across a wide range of XML files (organised however you want), and simply included in the configuration. The structure should be in a format that makes sense. Have a file/folder for Controllers, Facilities, etc etc. A heirarchy of related items.

With something more code-oriented, such as Autofac, you could easily create a host of container configuration providers to power your configuration. With Hiro, you don't really need to do much configuration at all.

Regardless of the container used, they all provide facilites for convention-over-configuration based registrations, so that should be your first stop in cleaning up registrations. A great example would be to register all classes whose name ends in 'Controller' in an MVC application.

Answer 2

Autofac and others (eg Ninject) employ a module concept for this exact purpose. http://code.google.com/p/autofac/wiki/StructuringWithModules may be what you're looking for.

Hth Nick