What is the difference between TypeScript decorators and middleware?

What is the difference between TypeScript decorators and middleware?

TypeScript decorators are special annotations that can modify classes, methods, or properties at design time. Middleware, on the other hand, is a function that processes requests in a web application, typically used in frameworks like Express.

Can you give me an example of a TypeScript decorator?

Sure! Here's a simple example of a class decorator that logs the class name:

function LogClass(target: Function) {
    console.log(`Class created: ${target.name}`);
}

@LogClass
class MyClass {}

How does middleware work in an Express application?

In Express, middleware functions have access to the request and response objects. They can modify the request, end the response, or call the next middleware in the stack. Here's a basic example:

app.use((req, res, next) => {
    console.log('Request received!');
    next(); // Pass control to the next middleware
});

When should I use decorators instead of middleware?

Use decorators when you want to add metadata or behavior to classes or methods at design time. Use middleware for handling requests and responses in a web application context.