If you've built any web application in Go, you've probably heard about middlewares. But what exactly are they?

A middleware is just a function that sits between your HTTP server and your route handlers. It can inspect, modify, or even stop a request before it reaches your main application logic.

Think of it as a pipeline.Every request passes through each middleware in order before hitting your handler, and the response travels back through them on the way out.

Example

A middleware accepts a handler and returns a new one:

func MyMiddleware ( next HandlerFunc ) HandlerFunc { return func ( c Context ) error { // runs before your handler err := c . Next ( next ) // runs after your handler return err } }

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c.Next()

When you register multiple middlewares, your framework doesn't run them independently. It builds a chain. Each middleware wraps the next one, like nested functions.…