This sample is for replacing JSON key by golang.
package main
import (
"encoding/json"
"fmt"
)
func main() {
json1 := `{"key1": "value1"}`
obj := map[string]interface{}{}
json.Unmarshal([]byte(json1), &obj)
fmt.Println(obj) // <-- map[key1:value1]
obj["key2"] = obj["key1"]
delete(obj, "key1")
fmt.Println(obj) // <-- map[key2:value1]
}