使用 net/http 构建子路由器的好方法

A good way to build a subrouter with net/http

我正在构建一个 API 服务器,它使用 net/http 处理多个路径。我想把它做成一个子路由器,但我不知道一个好的方法。

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)
    }
}

上面的实现好像有点多余。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 mux 与子路由器的 mux 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
}

用 net/http 构建一个简单的子路由器很难吗?我需要使用像 go-chi/chi or gorilla/mux 这样的 WAF 吗?

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,请执行以下操作。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))
}