如何在Go中编写简单的自定义http服务器？

Question

我是新手，试图编写自定义http server.Getting编译错误。我如何在我的代码中实现ServeHTTP方法？

我的代码：

package main 

import (
     "net/http" 
     "fmt" 
     "io" 
     "time" 
    ) 


func myHandler(w http.ResponseWriter, req *http.Request){ 
    io.WriteString(w, "hello, world!\n") 
} 


func main() { 

    //Custom http server 
    s := &http.Server{ 
     Addr:   ":8080", 
     Handler:  myHandler, 
     ReadTimeout: 10 * time.Second, 
     WriteTimeout: 10 * time.Second, 
     MaxHeaderBytes: 1 << 20, 
    } 

    err := s.ListenAndServe() 
    if err != nil { 
     fmt.Printf("Server failed: ", err.Error()) 
    } 
} 

错误而编译：

.\hello.go:21: cannot use myHandler (type func(http.ResponseWriter, *http.Request)) as type http.Handler in field value: 
    func(http.ResponseWriter, *http.Request) does not implement http.Handler (missing ServeHTTP method) 

Answer 1

你要么使用结构，并在其上定义ServeHTTP或者干脆换你的函数在HandlerFunc

s := &http.Server{ 
    Addr:   ":8080", 
    Handler:  http.HandlerFunc(myHandler), 
    ReadTimeout: 10 * time.Second, 
    WriteTimeout: 10 * time.Second, 
    MaxHeaderBytes: 1 << 20, 
} 

Answer 2

为了正常工作，myHandler应该是一个满足Handler Interface的对象，换句话说myHandler应该有称为ServeHTTP的方法。

例如，假设myHandler是用于显示当前时间的自定义处理程序。代码应该是这样的

package main 

import (
    "fmt" 
    "net/http" 
    "time" 
) 

type timeHandler struct { 
    zone *time.Location 
} 

func (th *timeHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) { 
    tm := time.Now().In(th.zone).Format(time.RFC1123) 
    w.Write([]byte("The time is: " + tm)) 
} 

func newTimeHandler(name string) *timeHandler { 
    return &timeHandler{zone: time.FixedZone(name, 0)} 
} 

func main() { 

    myHandler := newTimeHandler("EST") 
    //Custom http server 
    s := &http.Server{ 
     Addr:   ":8080", 
     Handler:  myHandler, 
     ReadTimeout: 10 * time.Second, 
     WriteTimeout: 10 * time.Second, 
     MaxHeaderBytes: 1 << 20, 
    } 

    err := s.ListenAndServe() 
    if err != nil { 
     fmt.Printf("Server failed: ", err.Error()) 
    } 
} 

运行此代码并在您的浏览器中访问​​。你应该看到类似这样的

The time is: Sat, 30 Aug 2014 18:19:46 EST 

（你应该看到不同的时间。）

希望这有助于格式化文本，

进一步阅读

A Recap of Request Handling in Go

Answer 3

结果： tonycai @ frog：〜$ curl“http://localhost:4000” 现在时间是：2018年1月12日星期五04:11:18 EST

但是，如何更改时区？从EST到CST