Golang : Covert map/slice/array to JSON or XML format

Problem : You have a data struct in map, slice or array format and you have to convert the data to JSON or XML format. How to do that? Solution : Convert the map, slice or array data to JSON with json.Marshal() function. In the struct, remember to add struct tags for JSON or XML. NOTE : Set Content-Type to application/json or application/xml when writing out as HTTP response. For example : package main import ( "encoding/json" "fmt" "net/http" ) type KeyPair struct { Id int `json:"id"` // <--- json struct tags Name string `json:"name"` // <--- json struct tags func Home(w http.ResponseWriter, r *http.Request) { KP := KeyPair{Id: 1, Name: "Adam" fmt.Println(KP) byte, err := json.Marshal(KP) // <---- here ! if err != nil { return w.Header().Set("Content-Type", "application/json") // <---- here ! fmt.Fprint(w, string(byte)) fmt.Println(string(byte)) func main() { http.HandleFunc("/", Home) http.ListenAndServe(":8080", nil) To convert struct data to XML, just change the encoder and field tags to XML equivalent. See https://www.socketloop.com/tutorials/golang-xml-to-json-example for guide. Happy coding!