用net / http构建子路由器的好方法

Question

我正在构建使用net/http处理多个路径的API服务器。我想将其构建为子路由器，但我不知道这样做的好方法。

目前，我的想法如下。

package main

import (
    "database/sql"
    "log"
    "net/http"
)

type Config struct {
    db *sql.DB
}

type UserRouter struct {
    mux *http.ServeMux
    cfg *Config
}

func (u *UserRouter) Create(w http.ResponseWriter, r *http.Request) {
    // process handler logic
    w.Write([]byte("Create"))
}

func (u *UserRouter) Delete(w http.ResponseWriter, r *http.Request) {
    // process handler logic
    w.Write([]byte("Delete"))
}

// NewUserRouter is subrouter.
func NewUserRouter(cfg *Config) *UserRouter {
    mux := http.NewServeMux()
    u := &UserRouter{
        mux: mux,
        cfg: cfg,
    }
    mux.HandleFunc("/user/create", u.Create)
    mux.HandleFunc("/user/delete", u.Delete)
    return u
}

func (u *UserRouter) ServeHTTP(w http.ResponseWriter, r *http.Request) {
    u.mux.ServeHTTP(w, r)
}

func main() {
    mux := http.NewServeMux()
    cfg := &Config{nil /* Describes settings such as PostgreSQL. */}
    mux.Handle("/user/", NewUserRouter(cfg))
    if err := http.ListenAndServe(":8080", mux); err != nil {
        log.Fatal(err)
    }
}

上面的实现似乎有点多余。但是，如果子路由器路径设置如下，HTTP服务器将无法正常工作。我认为这是因为传递给ListenAndServe的多路复用器与子路由器的多路复用器不同。

// NewUserRouter is subrouter.
func NewUserRouter(cfg *Config) *UserRouter {
    mux := http.NewServeMux()
    u := &UserRouter{
        mux: mux,
        cfg: cfg,
    }
-   mux.HandleFunc("/user/create", u.Create)
-   mux.HandleFunc("/user/delete", u.Delete)
+   mux.HandleFunc("/create", u.Create)
+   mux.HandleFunc("/delete", u.Delete)
    return u
}

很难用net / http构建一个简单的子路由器，我是否需要使用go-chi/chi或gorilla/mux这样的WAF？

Answer 1

如果您的目标是将用户处理程序的注册与其他处理程序分开，则可以执行以下操作。不需要子路由器。

type UserRouter struct {
    cfg *Config

    // prefix is the path prefix for the user handlers. Use this
    // value to construct paths to other user handlers.
    prefix string 
}

// RegisterUserHandler adds the user handlers to mux using the
// specified path prefix.
func RegisterUserHandler(cfg *Config, prefix string, mux *http.ServeMux)  {
    u := &UserRouter{cfg: cfg, prefix: prefix}
    mux.HandleFunc(prefix+"/create", u.Create)
    mux.HandleFunc(prefix+"/delete", u.Delete)
}

func main() {
    mux := http.NewServeMux()
    cfg := &Config{nil /* Describes settings such as PostgreSQL. */}
    RegisterUserHandler(cfg, "/user", mux)
    log.Fatal(http.ListenAndServe(":8080", mux))
}