go实现http服务三

通过map来保存你注册的 handler ， 底层通过ServeHTTP来进行转发。

每个handler只有一个方法ServeHTTP，所以可以在ServeHTTP中进行路由的转发

server3.go

package main

import (

        "io"

        "net/http"

        "log"

        "time"

)

var muxmap[string] func(http.ResponseWriter, *http.Request)

func main () {

        server := &http.Server{

              Addr:":6077",

              Handler:&NewHandler{},

              ReadTimeout:5 * time.Second,

       }

        // 路由注册

        mux = make(map[string]func(http.ResponseWriter, *http.Request))

        mux["/hello"] = sayThree

        mux["/say"]   = sayFive

        err := server.ListenAndServe()

        if err != nil {

                log.Fatal(err)

        }

}

type NewHandlerstruct {}

func (*NewHandler)ServeHTTP(w http.ResponseWriter, r *http.Request) {

        if fun, ok := mux[r.URL.String()]; ok {

                fun(w, r)

                return

        }    

        io.WriteString(w, "URL:" + r.URL.String())

}

func sayThree (w http.ResponseWriter, r *http.Request) {

        io.WriteString(w, "this is version 3")

}

func sayFive (w http.ResponseWriter, r *http.Request) {

        io.WriteString(w, "this is version 4")

}

go run server3.go