Question

My company is currently in the process of creating a large multi-tier software package in C#. We have taken a SOA approach to the structure and I was wondering whether anyone has any advice as to how to make it extensible by users with programming knowledge.

This would involve a two-fold process: approval by the administrator of a production system to allow a specific plugin to be used, and also the actual plugin architecture itself.

We want to allow the users to write scripts to perform common tasks, modify the layout of the user interface (written in WPF) and add new functionality (ie. allowing charting of tabulated data). Does anyone have any suggestions of how to implement this, or know where one might obtain the knowledge to do this kind of thing?

I was thinking this would be the perfect corner-case for releasing the software open-source with a restrictive license on distribution, however, I’m not keen on allowing the competition access to our source code.

Thanks.

EDIT: Thought I’d just clarify to explain why I chose the answer I did. I was referring to production administrators external to my company (ie. the client), and giving them someway to automate/script things in an easier manner without requiring them to have a full knowledge of c# (they are mostly end-users with limited programming experience) – I was thinking more of a DSL. This may be an out of reach goal and the Managed Extensibility Framework seems to offer the best compromise so far.

Answer 1

I would take a look at the MEF initiative from Microsoft. It’s a framework that lets you add extensibility to your applications. It’s in beta now, but should be part of .Net 4.0.

Microsoft shares the source, so you can look how it’s implemented and interface with it. So basically your extensibility framework will be open for everyone to look at but it won’t force you to publish your application code or the plug-ins code.