import (
	"encoding/json"
	"log"
	"net/http"
	"time"
)
func apiClockHandler(w http.ResponseWriter, r *http.Request){
	type ResponseBody struct {
		Time time.Time `json:"time"`
	}
	rb := &ResponseBody {
		Time: time.Now(),
	}
	w.Header().Set("Content-type", "application/json")
	if err := json.NewEncoder(w).Encode(rb); err != nil {
		log.Fatal(err)
	}
}
func main(){
	http.HandleFunc("/api/clock", apiClockHandler)
	log.Fatal(http.ListenAndServe(":8080",nil))
}
http://192.168.34.10:8080/api/clock

OK, ある程度のところまで来た