Interface Segregation Principle (ISP) in React Development
How to build cleaner components
Welcome back to our SOLID principles in the React series! So far, we’ve covered:
✅ S: Single Responsibility Principle (SRP): Keep components focused.
✅ O: Open/Closed Principle (OCP): Make extensions easy, not modifications.
✅ L: Liskov Substitution Principle (LSP): Keep components interchangeable without breaking behavior.
Today, we’re diving into the Interface Segregation Principle (ISP)—a principle that helps keep our React components and interfaces lean, modular, and easier to maintain.
If SOLID principles were a gym for your code, ISP would be the exercise that trims down bloated, unfocused interfaces. Let’s break it down and then apply it to real-world React examples.
What is the Interface Segregation Principle (ISP)?
ISP is one of the five SOLID principles from object-oriented programming (OOP), but it’s just as relevant in React.
In simple terms:
“A class (or component) should not be forced to depend on interfaces it does not use.”
In React terms:
A component should only receive the props it actually needs.
Interfaces (types) should be small and specific, not overloaded with unrelated properties.
Hooks should return only the data relevant to their purpose.
If an interface has too many properties, components will be bloated, harder to reuse, and difficult to maintain.
In simple terms, ISP states that an interface should only have the methods and properties relevant to a specific use case. In React, this means breaking down component props and interfaces into smaller, focused ones. This improves maintainability, reusability, and readability.
Why Should React Developers Care?
Before we dive into code, let's talk about why this matters in real-world React development:
Easier Testing: When components have fewer responsibilities, they're much easier to test. You don't have to mock a bunch of unused props just to test one feature.