Services Layer

In my previous posts I showed layers and components, and layers and tiers.  In this post, I'll show the services layer in a layered architecture.

Services Layer
Here's a visual example of a services layer, where the application is exposing services:

ServicesLayer

Note that services don't need to be "web" services.

Key Services Layer Components
Here's the key components of a services layer:

  • Service Interfaces. The service interface acts as a facade that exposes the business logic to potential consumers.  The definition of the set of messages that must be exchanged with a service in order for the service to perform a specific business task is the contract.
  • Message Types. Message Types are “message contracts” for communication between service consumers and providers.  They wrap business entity components into specific messages for the calling service.

Additional Resources

My Related Posts

patterns & practices App Arch Guide 2.0 Project

Layers and Components

Layers and Tiers

App Arch Meta Frame

Scenario Frames for Presentation, Business, Data and Services