Patterns for non-layered applications
- by Paul Stovell
In Patterns of Enterprise Application Architecture, Martin Fowler writes:
This book is thus about how you
decompose an enterprise application
into layers and how those layers work
together. Most nontrivial enterprise
applications use a layered
architecture of some form, but in some
situations other approaches, such as
pipes and filters, are valuable. I
don't go into those situations,
focussing instead on the context of a
layered architecture because it's the
most widely useful.
What patterns exist for building non-layered applications/parts of an application? Take a statistical modelling engine for a financial institution. There might be a layer for data access, but I expect that most of the code would be in a single layer. Would you still expect to see Gang of Four patterns in such a layer? How about a domain model? Would you use OO at all, or would it be purely functional?
The quote mentions pipes and filters as alternate models to layers. I can easily imagine a such an engine using pipes as a way to break down the data processing. What other patterns exist? Are there common patterns for areas like task scheduling, results aggregation, or work distribution? What are some alternatives to MapReduce?
