用Go语言建立http-server响应对JSON数据对象进行编码与解码

cp /share/tar/go1.12.9.linux-amd64.tar.gz .
 
tar -C /usr/local -xzvf go1.12.9.linux-amd64.tar.gz
 
echo export PATH=$PATH:/usr/local/go/bin >> /etc/profile
 
source /etc/profile
 
go version

#使用vim创建json.go文件，内容如下
package main
 
import (
    "encoding/json"
    "fmt"
    "net/http"
)
 
type User struct {
    Firstname string `json:"firstname"`
    Lastname  string `json:"lastname"`
    Age       int    `json:"age"`
}
 
func main() {
    http.HandleFunc("/decode", func(w http.ResponseWriter, r *http.Request) {
        var user User
        json.NewDecoder(r.Body).Decode(&user)
 
        fmt.Fprintf(w, "%s %s is %d years old!", user.Firstname, user.Lastname, user.Age)
    })
 
    http.HandleFunc("/encode", func(w http.ResponseWriter, r *http.Request) {
        peter := User{
            Firstname: "John",
            Lastname:  "Doe",
            Age:       25,
        }
 
        json.NewEncoder(w).Encode(peter)
    })
 
    http.ListenAndServe(":80", nil)
}

go run json.go &

curl -s -X POST -d '{"firstname":"Elon","lastname":"Mars","age":48}' http://localhost/decode

curl -s http://localhost/encode