Architecture and protocol review

Architecture (v2)

After changing the bob client, our system architecture looks like this:

• The backend architecture changed from a single component to a cluster of 5 components.
• Each component is hosted at a different base URL.
• Despite the changes, the backend still delivers the identical resource and their relationships

  

• The bob client's knowledge of the original URL structure caused it to no longer function after the backend changes
  • i.e. bob was bound to the service architecture, which has a high likelihood of change
• The alice client continued to operate the same as if nothing happened
  • • i.e. alice was bound to the domain model, which maps to business entities. As long as the business does the same business, the domain model is far less likely to change.

Protocol

Looking only at the scripted steps the prior sections walked you through, the protocol between client and service can be shown as this:

Note

Even though the backend architecture changed, the protocol, which is based on the domain model, can be delivered in the same fashion