MVC Architecture & API Versioning

Concept#

Model-View-Controller (MVC) Pattern#

In backend APIs, the MVC pattern organizes code by separating concerns into distinct layers:

  ┌────────────────────────────────────────────────────────┐
  │  Client Request ──▶ Route ──▶ Controller ──▶ Model     │
  │   (HTTP GET)                  (Validates)   (Database) │
  └────────────────────────────────────────────────────────┘

1. Model: Manages data structures and database operations (e.g. Mongoose schema or Prisma Client).
2. View (or Presenter): Formats the response returned to the client (in JSON APIs, this is the structured JSON return shape).
3. Controller: Handles request validation, calls Model methods, and sends response payloads back to views.

API Versioning Strategies#

When releasing breaking changes to a public API, existing clients must not crash. Versioning ensures backward compatibility: