[go]net/http

返回数据

- 最简单的http服务

package main

import (

	"net/http"

)

func main() {

	http.ListenAndServe(":8080", nil)

}

返回字符串

- 挂载路由节点

//例1:

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		w.Write([]byte("hello http"))

	})

	http.ListenAndServe(":8080", nil)

}

//例2

package main

import (

	"net/http"

)

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		io.WriteString(w, "hello world")

	})

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

}

//例3:

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		fmt.Fprint(w, "hello world2")

	})

	http.ListenAndServe(":8080", nil)

}

- 启动http接口

package main

import (

	"io"

	"log"

	"net/http"

)

func main() {

	h1 := func(w http.ResponseWriter, _ *http.Request) {

		io.WriteString(w, "Hello from a HandleFunc #1!\n")

	}

	h2 := func(w http.ResponseWriter, _ *http.Request) {

		io.WriteString(w, "Hello from a HandleFunc #2!\n")

	}

	http.HandleFunc("/", h1)

	http.HandleFunc("/endpoint", h2)

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

}

返回json

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		w.Header().Set("content-type", "application/json; charset=utf-8")

		w.Write([]byte(`{"code":-1, "msg":"no such file我"}`))

	})

	http.ListenAndServe(":8080", nil)

}

- 例子: 读取data.json,返回json

- data.json

[

  {

    "name": "mm",

    "age": 22

  }

]

type User struct {

	Name string `json:"name"`

	Age  int    `json:"age"`

}

var data []User

func LoadData() {

	var content, err = ioutil.ReadFile("data.json")

	if err != nil {

		fmt.Println(err.Error())

	}

	json.Unmarshal(content, &data)

	fmt.Println(data)

}

func main() {

	LoadData()

	// CRUD endpoint functions

	u := func(w http.ResponseWriter, _ *http.Request) {

		w.Header().Set("Content-Type", "application/json")

		json.NewEncoder(w).Encode(data)// 1.json写入io.Writer/os.Stdout

								       // 2.[普通marshell]json和data之间转换

	}

	http.HandleFunc("/user", u)

	http.ListenAndServe(":8080", nil)

}

获取参数

// GET localhost:8080/?name=mm&age=22

Content-Type: "" //request的Content-Type值为""

//参数携带在了url(Query String Parameters)

name=m1&age=22

// body内容为空

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		r.ParseForm() //将参数解析到一个map里

		fmt.Println(r.Form) //map[age:[22] name:[mm]]

		name := r.Form["name"][0]

		fmt.Println(name)

		io.WriteString(w, "hi")

	})

	http.ListenAndServe(":8080", nil)

}

//mm

//GET localhost:8080/?name=m1&name=m2&age=22

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		r.ParseForm()

		fmt.Println(r.Form) //map[age:[22] name:[m1 m2]]

		name1 := r.Form["name"][0]

		name2 := r.Form["name"][1]

		fmt.Println(name1, name2)

		io.WriteString(w, "hi")

	})

	http.ListenAndServe(":8080", nil)

}

//m1 m2

// GET localhost:8080/?name=mm&age=22

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		r.ParseForm()

		name := r.Form.Get("name") //使用url.Values(map)封装的GET方法取值

		age := r.Form.Get("age")

		fmt.Println(name, age)

		io.WriteString(w, "hi")

	})

	http.ListenAndServe(":8080", nil)

}

//mm 22

- form提交默认是get.(和GET携带参数处理方式一样)

	<body>

	<form action="http://localhost:8080/">

		<input type="text" name="name">

		<input type="text" name="age">

		<input type="submit">

	</form>

	</body>

Content-Type: "" //request的Content-Type值为""

//数据(参数)携带在了url(Query String Parameters )

name=admin&age=123456

// body内容为空

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		r.ParseForm()       //将参数解析到一个map里

		fmt.Println(r.Form) //map[age:[123456] name:[admin]]

		io.WriteString(w, "hi")

	})

	http.ListenAndServe(":8080", nil)

}

- 表单请求

	<body>

	<form action="http://localhost:8080/" method="post">

		<input type="text" name="name">

		<input type="text" name="age">

		<input type="submit">

	</form>

	</body>

//默认将request的Content-Type设置为

	Content-Type: application/x-www-form-urlencoded

//将数据携带在了body(Form Data):

name=m1&age=22

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		body, _ := ioutil.ReadAll(r.Body)

		fmt.Println(string(body)) //name=m1&age=22

		io.WriteString(w, "hi")

	})

	http.ListenAndServe(":8080", nil)

}

- 上面这种情况,解析表单参数

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		r.ParseForm() //将参数解析到一个map里

		fmt.Println(r.Form) //map[age:[22] name:[mm]]

		io.WriteString(w, "hi")

	})

	http.ListenAndServe(":8080", nil)

}

- 解析post body: json data

POST localhost:8080

Content-Type: application/json;charset=UTF-8

{

  "name": "m1",

  "age": 22

}

// Content-Type: application/json;charset=UTF-8

//数据携带在body(Request Payload)

{"name":"mm","age":22}

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		body, _ := ioutil.ReadAll(r.Body)

		//fmt.Fprintf(w, "%s", body)

		user := User{}

		err := json.Unmarshal(body, &user)

		if err != nil {

			fmt.Println(err)

		}

		fmt.Println(user)

	})

	http.ListenAndServe(":8080", nil)

}

文件上传下载

文件下载

- 简单的web 文件服务

func main() {

	// Simple static webserver:

	log.Fatal(http.ListenAndServe(":3001", http.FileServer(http.Dir("."))))

}

- 伪url访问真实目录

func main() {

	// To serve a directory on disk (/tmp) under an alternate URL

	// path (/tmpfiles/), use StripPrefix to modify the request

	http.Handle("/tmpfiles/", http.StripPrefix("/tmpfiles/", http.FileServer(http.Dir("."))))

	http.ListenAndServe(":3001", nil)

}

文件上传

- request:

Content-Type: multipart/form-data;

- 文件上传的表单

Content-Disposition 属性是作为对下载文件的一个标识字段

如果有type=file的话，就要用到multipart/form-data了。

	浏览器会把整个表单以控件为单位分割，

	并为每个部分加上

		Content-Disposition(form-data或者file),

		Content-Type(默认为text/plain),

		name(控件name)等信息，

		并加上分割符(boundary)。

<body>

<form action="http://localhost:8080/" method="post" enctype="multipart/form-data">

    <input type="file" name="file">

    <input type="submit">

</form>

</body>

- 请求body: 内容里Content-Type会自动感知为对应文件类型

------WebKitFormBoundary9Px0BT0GcBlQEiUO

Content-Disposition: form-data; name="file"; filename="app.json"

Content-Type: application/json

{

  "name": "Start on Heroku: Go",

  "description": "Go Getting Started Example App",

  "keywords": [

    "getting-started",

    "go",

    "sample",

    "example"

  ],

  "image": "heroku/go:1.6",

  "mount_dir": "src/github.com/heroku/go-getting-started",

  "website": "http://github.com/heroku/go-getting-started",

  "repository": "http://github.com/heroku/go-getting-started"

}

------WebKitFormBoundary9Px0BT0GcBlQEiUO--

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		body, _ := ioutil.ReadAll(r.Body)

		fmt.Println(string(body))

		w.Write([]byte("hi"))

		//r.ParseMultipartForm(32 << 20)

		//file, handler, err := r.FormFile("file")

		//if err != nil {

		//	w.WriteHeader(http.StatusInternalServerError)

		//	w.Write([]byte("解析表单出错"))

		//	return

		//}

		//defer file.Close()

		//f, err := os.OpenFile(handler.Filename, os.O_WRONLY|os.O_CREATE, 0666)

		//if err != nil {

		//	w.WriteHeader(http.StatusInternalServerError)

		//	w.Write([]byte("写入文件出错"))

		//	return

		//}

		//defer f.Close()

		//io.Copy(f, file)

	})

	http.ListenAndServe(":8080", nil)

}

如果传的是图片, 则会展示一些乱码

常用方法

区分http方法: r.Method

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		if r.Method == "GET" {

			io.WriteString(w, "get")

		} else if r.Method == "POST" {

			io.WriteString(w, time.Now().Format("post: 2006-01-02 15:04:05"))

		}

	})

	http.ListenAndServe(":8080", nil)

}

- w.Write后面语句会执行

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		w.Write([]byte("hi"))

		fmt.Println("123213123")

	})

	http.ListenAndServe(":3000", nil)

}

//return后不再执行

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		w.Write([]byte("hi"))

		return

		fmt.Println("123213123")

	})

	http.ListenAndServe(":3000", nil)

}

- 读文件,返回文件

func main() {

	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

		data, err := ioutil.ReadFile("./static/view/signup2.html")

		if err != nil {

			w.WriteHeader(http.StatusNotFound)

			w.Write([]byte(err.Error()))

			return

		}

		w.Write(data)

	})

	http.ListenAndServe(":3000", nil)

}

r.Method == "GET"

time.Now().Format("2006-01-02 15:04:05")

//文件操作

os.Create(fileMeta.Location)

io.Copy(newFile, file)

os.Remove(fMeta.Location)

ioutil.ReadFile("./static/view/index.html")

os.Open(fm.Location)

ioutil.ReadAll(f)

newFile.Seek(0, 0)

//获取GET参数

// - 方法1

r.ParseForm()

op := r.Form.Get("op")

// - 方法2

r.ParseForm()

op := r.Form["op"][0]

// 小结: 表单post过来的格式和 get方法通过路径携带参数  提交过来的格式 是一致的.

//获取表单提交字段数据

// - 方法1

r.ParseForm()

op := r.Form.Get("op")

// - 方法2

r.ParseForm()

filehash := r.Form["filehash"][0]

//表单传文件

file, head, err := r.FormFile("file")  // <form action="http://localhost:8081/upload" method="post" enctype="multipart/form-data">

w.Write([]byte("Upload Failed."))

w.Write([]byte(`{"code":-1,"msg":"no such file"}`))

io.WriteString(w, "internel server error")

//设置下载头

w.Header().Set("Content-Type", "application/octect-stream")

w.Header().Set("content-disposition", "attachment; filename=\""+fm.FileName+"\"")

//设置跨域头

w.Header().Set("Access-Control-Allow-Origin", "*")             //允许访问所有域

w.Header().Add("Access-Control-Allow-Headers", "Content-Type") //header的类型

w.Header().Set("content-type", "application/json")

//TODO: 设置全局跨域中间件

w.WriteHeader(http.StatusOK)

w.WriteHeader(http.StatusInternalServerError)

w.WriteHeader(http.StatusMethodNotAllowed)

w.WriteHeader(http.StatusForbidden)

http.Redirect(w, r, "/static/view/home.html", http.StatusFound)

fmt.Println(err.Error())

// http包基础使用

http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {

})

http.ListenAndServe(":3000", nil)

// http包进阶使用

//初始化路由

mux = http.NewServeMux()

mux.HandleFunc("/job/save", handleJobSave)

//设置静态目录

staticDir = http.Dir(G_config.WebRoot)

staticHandler = http.FileServer(staticDir)

mux.Handle("/", http.StripPrefix("/", staticHandler))

listener, err = net.Listen("tcp", ":" + strconv.Itoa(G_config.ApiPort));

//创建http服务器

httpServer = &http.Server{

    ReadTimeout: time.Duration(G_config.ApiReadTimeout) * time.Millisecond,

    WriteTimeout: time.Duration(G_config.ApiWriteTimeout) * time.Millisecond,

    Handler: mux,

}

go httpServer.Serve(listener)

net/http模块架构

前后端交互数据

通过表单提交

// 前端表单提交

<form action="http://localhost:8000/" method="post">

    <input type="text" name="username">

    <input type="text" name="password">

    <input type="submit">

</form>

//后端接收

r.ParseForm()

username := r.Form.Get("username") //接收到的都是字符串

前端ajax post提交json

// 前端ajax post提交json

<!DOCTYPE html>

<html lang="en">

<head>

    <meta charset="UTF-8">

    <title>test</title>

</head>

<body>

<div id="app">

    <button @click="postData">postData</button>

</div>

<script src="node_modules/vue/dist/vue.js"></script>

<script src="node_modules/axios/dist/axios.js"></script>

<script>

    let vm = new Vue({

        el: "#app",

        methods: {

            postData() {

                axios.post("http://localhost:8000/", {

                    "username": "m1",

                    "password": 123456

                })

            }

        }

    });

</script>

</body>

</html>

参考

type LoginInfo struct {

	Username string `json:username`

	Password int    `json:password`

}

body, _ := ioutil.ReadAll(r.Body)

var loginInfo LoginInfo

json.Unmarshal(body, &loginInfo)

fmt.Println(loginInfo)

巴特西

[go]net/http

返回数据

获取参数

文件上传下载

常用方法

net/http模块架构

前后端交互数据

通过表单提交

前端ajax post提交json

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