http JSON

struct 을 JSON string 으로 변환

type Book struct {     Title string `json:"title"`     Author string `json:"author"` } // an instance of our Book struct book := Book{Title: "Learning Concurreny in Python", Author: "Elliot Forbes"} byteArray, err := json.Marshal(book) if err != nil {     fmt.Println(err) } fmt.Println(string(byteArray))

 

struct 과 struct 속의 struct 을 JSON string 으로 변환

type Book struct {     Title string `json:"title"`     Author Author `json:"author"` } type Author struct {     Sales int `json:"book_sales"`     Age int `json:"age"`     Developer bool `json:"is_developer"` } author := Author{Sales: 3, Age: 25, Developer: true} book := Book{Title: "Learning Concurrency in Python", Author: author} byteArray, err := json.Marshal(book) // //json.MarshalIndent(book, "", "  ") if err != nil {     fmt.Println(err) } fmt.Println(string(byteArray)) $ go run main.go {"title":"Learning Concurrency in Python","author":{"book_sales":3,"age":25,"is_developer":true}}

 

JSON string 을 struct 으로 변환

type SensorReading struct {     Name string `json:"name"`     Capacity int `json:"capacity"`     Time string `json:"time"` } jsonString := `{"name": "battery sensor", "capacity": 40, "time": "2019-01-21T19:07:28Z"}` var reading SensorReading err := json.Unmarshal([]byte(jsonString), &reading) fmt.Printf("%+v\n", reading)

 

웹 api JSON
client

$ curl -X POST http://localhost:8080/decode \    -d '        {"name": "tomas",   "age": 31}        {"name": "charles", "age": 48}     '

 

Server

package main import (            "encoding/json"            "errors"            "fmt"            "io"            "log"            "net/http"            "os" ) type Person struct {            Name string `json: "name"`            Age int `json: "age"` } func decodeHandler(w http.ResponseWriter, r *http.Request) {            dec := json.NewDecoder(r.Body)            var e *json.UnmarshalTypeError            for {                       var p Person                       err := dec.Decode(&p)                       if err == io.EOF {                                  break                       }                       if errors.As(err, &e) {                                  log.Println(err)                                  continue                       }                       if err != nil {                                  http.Error(w, err.Error(), http.StatusBadRequest)                                  return                       }                       fmt.Println(p.Name, p.Age)            }            fmt.Fprintf(w, "OK") } func sayHello(w http.ResponseWriter, r *http.Request) {            fmt.Fprintf(w, "Hi there!") } func setupHandler(mux *http.ServeMux) {            mux.HandleFunc("/", sayHello)            mux.HandleFunc("/person", decodeHandler) } func main() {            listenAddr := os.Getenv("LISTEN_ADDR")            if len(listenAddr) == 0 {                       listenAddr = ":8080"            }            mux := http.NewServeMux()            setupHandler(mux)            log.Fatal(http.ListenAndServe(listenAddr, mux)) }