update mapping from server in editor | unity3d

using UnityEngine;
using UnityEditor;
using System.Xml;
using System.Collections;
using UnityEngine.Networking;

namespace g144.debug
{
    [ExecuteInEditMode]
    public class gameMapping_topMenu : MonoBehaviour
    {
        private string titlePar = "markersHouse";

        private static gameMapping_topMenu cache;

        private void OnEnable()
        {
            cache = this;
        }

        [MenuItem("mapping/Update house markers")]
        public static void updateHouseMarkers()
        {
            cache.reqUpdateMarkers();
        }

        private void reqUpdateMarkers()
        {
            StartCoroutine(getMarkersInfo());
        }

        private IEnumerator getMarkersInfo()
        {
            Debug.LogWarning("send request. please wait...");

            string url = "http://127.0.0.1/house.php";

            WWWForm form = new WWWForm();
            form.AddField("action", "getMarkers"); // response snapshot https://imgur.com/a/IzchLvB

            UnityWebRequest req = UnityWebRequest.Post(url, form);
            yield return req.SendWebRequest();

            webResponse resp = GlobalEnv.parseWebReq(req); // method snapshot https://imgur.com/a/EaTgZY1

            Transform markerPar = GameObject.Find(titlePar).transform;

            if (markerPar)
            {
                int countOldMarkers = markerPar.childCount;

                for (int i = 0; i < countOldMarkers; i++)
                    DestroyImmediate(markerPar.GetChild(0).gameObject);
            }
            else
                markerPar = new GameObject(titlePar).transform;

            if (resp.isSuccess)
            {
                XmlNodeList nodes = resp.node.ChildNodes;

                for(int i = 0; i < nodes.Count; i++)
                {
                    string[] cord = nodes[i]["cord"].InnerText.Split(',');

                    Transform marker = new GameObject(string.Format("marker_{0}", i)).transform;
                    marker.parent = markerPar;
                    marker.position = new Vector3(float.Parse(cord[0]), float.Parse(cord[1]), float.Parse(cord[2]));
                }
            }
            else
                Debug.LogWarning("No find markers");
        }
    }
}