I want to include midi functionality through DryWetMIDI, but that got me thinking: I'm creeping in so many features and dependencies, perhaps some users don't want all that functionality. Or perhaps they want custom features that I'm not adding. I feel plugins would be a good solution to this, besides being fun to implement.

Key2Joy.Plugin.Midi in this branch shows an early example (e.g: Key2Joy.Plugin.Midi /Mapping/Actions/GetHelloWorldAction.cs). I hope to expand it to a plugin that will add Midi Controller trigger and some Midi writing action capabilities.

Plugins would add:

• More customization options
• Lower barrier to contribute
• Possibility to add features without bloating the main project
• Possibility to add features without having to wait for me to merge your PR
• Ability to license plugin code differently from the main project
• Ability to 'sandbox' plugin code

Some negatives:

• More complexity
• More work to maintain
• Versioning challenges
• Possible slowdown from inter-process communication
• Harder to debug: exceptions inside a plugin (or even inside the PluginHost) are hard to catch or notice.

PR Checklist

• Security risks:
  • Mitigated with code (using AppDomain)
  • Vulnerabilities Tested
  • Users informed
• Examples and documentation:
  • A plugin example (Key2Joy.Plugin.HelloWorld)
  • Plugin Hosting doesn't feel any slower. Either through optimizations or by pre-loading plugin content (upon enabling the profile).
  • Moved the FFMPEG dependency to a plugin (Key2Joy.Plugin.Ffmpeg) while tackling AnimationFromImagesAction fails due to ffprobe.exe missing #36
  • Have BuildMarkdownDocs also generate plugin markdowns

Postponed

I've crossed these off the original PR checklist. I'm postponing them until I've fixed most bugs people are currently encountering:

• Considered how to version plugins and implement versioning
• Designed a way to share and distribute plugins
• Written documentation on how to create a plugin
• Diagram of Plugin <- PluginHost -> Key2Joy interaction
• A plugin example that adds Midi Controller trigger and Midi writing action capabilities (Key2Joy.Plugin.Midi)
• Moved one of the scripting languages to a plugin (to serve as an example and test case for complex plugins)

These postponed points have been moved to #51 and #52 for tracking)