Structuring Routes and Controllers: The MVC Pattern
Explore how to separate routing and business logic using the MVC pattern with Express and Mongoose. Learn to keep route files focused on endpoints while controllers handle logic, improving maintainability and scalability for MERN stack applications.
The previous lessons built create, read, update, and delete logic, but often as handlers defined inline where the route was declared. That works for a handful of endpoints. As an application grows toward dozens of routes across products, users, orders, reviews, and categories, mixing routing and logic in one place becomes hard to read, test, and extend. This lesson reorganizes that code using the model-view-controller (MVC) pattern introduced in the scaffold lesson and explains why the separation pays off.
The MVC structure established here is the organization used for the rest of the course, including the mid-course projects and the capstone, so it is worth getting comfortable with now.
Note: This lesson is about code organization, not new database operations. The Mongoose calls are the same ones you have already run; what changes is where they live.
To make the structure concrete, the next visual should show how a request travels from a route file ...