SimpleCQRS-FSharp

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Simple CQRS on F# (F-Sharp) 3.0

Based on Greg Young's CQRS: https://github.com/gregoryyoung/m-r/tree/master/SimpleCQRS

CQRS is Command and Query Responsibility Segregation -pattern. If you don't know that, use Google or look http://martinfowler.com/bliki/CQRS.html I have separated command side and query side as different projects.

This is F# solution. Compared to C#:

• Simpler source code
• No need for any "InfrastructureCrap"
• Domain objects doesn't need to have parameter less constructors
• Interactive-driven development

What you will need to run this:

• Visual Studio 11 (Beta): http://www.microsoft.com/visualstudio/11/en-us

Optional:

• Reactive extensions: http://msdn.microsoft.com/en-us/data/gg577609

There are two versions of event storage:

1. Pure F# as EventStorage.fs
   • Uses pure .NET Events with F# Observable as event bus
   • Uses MailboxProcessor ("agents"/message passing) as event storage
2. F# with Reactive Extensions as EventStorageRx.fs
   • Uses reactive framework Subject<T> as event bus
   • Uses reactive framework ReplaySubject<T> as event storage Although technical concept is different, the functionality is identical.

You can run this with F# interactive, directly from files and/or using Script.fsx.

This QuerySide is just in-memory one as in Greg's example. I suggest using F# Type Providers in QuerySide with real database...