𝗕𝘂𝗶𝗹𝗱𝗶𝗻𝗴 𝗚𝗼 𝗠𝗶𝗱𝗱𝗹𝗲𝘄𝗮𝗿𝗲 𝗙𝗿𝗼𝗺 𝗦𝗰𝗿𝗮𝘁𝗰𝗵

𝗕𝘂𝗶𝗹𝗱𝗶𝗻𝗴 𝗚𝗼 𝗠𝗶𝗱𝗱𝗹𝗲𝘄𝗮𝗿𝗲 𝗙𝗿𝗼𝗺 𝗦𝗰𝗿𝗮𝘁𝗰𝗵

Every Go web framework uses middleware. Gin and Echo have it. Most tutorials teach you how to use it. Few teach you how it works.

Go HTTP logic relies on one interface: http.Handler.

A middleware is a function. It takes a handler and returns a handler. It wraps the next step in the process. It runs code before or after the main handler.

Manual wrapping is messy. You end up with nested functions. A Chain function fixes this. It takes a slice of middleware. It applies them in the right order.

You build production tools with this pattern:

• Logging: Track method, path, and duration.
• Recovery: Catch panics to stop server crashes.
• Auth: Validate tokens and pass user IDs.
• Timeout: Cancel requests taking too long.

This pattern is not magic. It is a series of nested function calls.

You do not always need a framework. The standard library handles most API needs.

Source: https://dev.to/shayan_holakouee/building-a-nethttp-middleware-chain-from-scratch-in-go-346b