Services

Services

Handler

There are a couple of concepts related to services.

• http.Handler

The core interface for handline HTTP request.

type Handler interface {
    ServeHTTP(ResponseWriter, *Request)
}

Handlerfunc

You can turn a function (with the right signature) into a type, that satisfies http.Handler.

• http.HandlerFunc

The HandlerFunc type is an adapter to allow the use of ordinary functions as HTTP handlers. If f is a function with the appropriate signature, HandlerFunc(f) is a Handler that calls f.

With first class functions, it is possible to start an HTTP handler with a single (long) line.

HandleFunc

If we type http.HandleFunc, we are working on the DefaultServeMux, a http.ServeMux added for convenience in the http package.

ServeMux is an HTTP request multiplexer. It matches the URL of each incoming request against a list of registered patterns and calls the handler for the pattern that most closely matches the URL.

The ServeMux is itself an HTTP handler, as it implements ServeHTTP.

Code Review

• Example 1
• Example 2
• Example 3
• Example 4
• Example 4
• Example 5
• Example 6
• Example 7
• Example 8
• Example 9
• Example 10
• Example 11

Exercises

• Debug Handler (Answer)

Project

A todo web application.

• todosvc