第13课: Web开发与HTTP服务

简单HTTP服务器

func handler(w http.ResponseWriter, r *http.Request) {
    fmt.Fprintf(w, "Hello, World!")
}

func main() {
    http.HandleFunc("/", handler)
    http.ListenAndServe(":8080", nil)
}

路由处理

func main() {
    http.HandleFunc("/", homeHandler)
    http.HandleFunc("/api/users", usersHandler)
    http.HandleFunc("/api/posts", postsHandler)

    log.Fatal(http.ListenAndServe(":8080", nil))
}

JSON API

type User struct {
    ID   int    `json:"id"`
    Name string `json:"name"`
}

func usersHandler(w http.ResponseWriter, r *http.Request) {
    users := []User{
        {ID: 1, Name: "Alice"},
        {ID: 2, Name: "Bob"},
    }

    w.Header().Set("Content-Type", "application/json")
    json.NewEncoder(w).Encode(users)
}

中间件

func loggingMiddleware(next http.Handler) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        log.Printf("%s %s", r.Method, r.URL.Path)
        next.ServeHTTP(w, r)
    })
}

func main() {
    mux := http.NewServeMux()
    mux.HandleFunc("/", handler)

    http.ListenAndServe(":8080", loggingMiddleware(mux))
}