From 6285ccaaa6f9cf375b9e9f3765a6d725ebaf2da9 Mon Sep 17 00:00:00 2001
From: "Hung-Han (Henry) Chen" <chenhungh@gmail.com>
Date: Mon, 22 Nov 2021 16:27:35 +0200
Subject: [PATCH] Add whenCanResolveDomainName

Signed-off-by: Hung-Han (Henry) Chen <chenhungh@gmail.com>
---
 src/common/k8s-api/kube-api.ts | 32 ++++++++++++++++++++++----------
 1 file changed, 22 insertions(+), 10 deletions(-)

diff --git a/src/common/k8s-api/kube-api.ts b/src/common/k8s-api/kube-api.ts
index d06fa13b7b..bbf156d31a 100644
--- a/src/common/k8s-api/kube-api.ts
+++ b/src/common/k8s-api/kube-api.ts
@@ -40,6 +40,8 @@ import { Agent, AgentOptions } from "https";
 import type { Patch } from "rfc6902";
 import electron from "electron";
 import { ipcMainOn } from "../ipc";
+import { promises as dns } from "dns";
+import retry from "async-retry";
 
 export interface IKubeApiOptions<T extends KubeObject> {
   /**
@@ -555,6 +557,10 @@ export class KubeApi<T extends KubeObject> {
     this.watchingNetworkStatus = true;
   }
 
+  private whenCanResolveDomainName(url = "https://k8slens.dev/", retryOptions: Parameters<typeof retry>[1]) {
+    return retry(() => dns.resolve(url), retryOptions);
+  }
+
   watch(opts: KubeApiWatchOptions = { namespace: "", retry: false }): () => void {
     let errorReceived = false;
     let timedRetry: NodeJS.Timeout;
@@ -595,16 +601,22 @@ export class KubeApi<T extends KubeObject> {
       electron.powerMonitor.once("resume", () => {
         clearTimeout(timedRetry);
         timedRetry = setTimeout(() => {
-          if (this.networkOnline) {
-            logger.info(`[KUBE-API] system resumed, resume watching of ${watchUrl}...`);
-            this.watch({ ...opts, namespace, callback, watchId, retry: true });    
-          } else {
-            logger.info(`[KUBE-API] system resumed but network appears to be offline, resume watching when online.`);
-            electron.ipcMain.once("network:online", () => {
-              logger.info(`[KUBE-API] network on line, resume watching of ${watchUrl}...`);
-              this.watch({ ...opts, namespace, callback, watchId, retry: true });
-            });
-          }
+          const url = "https://k8slens.dev/"; // url to check if domain names are resolvable.
+
+          this.whenCanResolveDomainName(url, { retries: 10 }).then(() => {
+            if (this.networkOnline) {
+              logger.info(`[KUBE-API] system resumed, resume watching of ${watchUrl}...`);
+              this.watch({ ...opts, namespace, callback, watchId, retry: true }); 
+            } else {
+              logger.info(`[KUBE-API] system resumed but network appears to be offline, resume watching when online.`);
+              electron.ipcMain.once("network:online", () => {
+                logger.info(`[KUBE-API] network on line, resume watching of ${watchUrl}...`);
+                this.watch({ ...opts, namespace, callback, watchId, retry: true });
+              });
+            }
+          }).catch((error) => {
+            logger.error(`[KUBE-API] error resolving domain name ${url}`, error);
+          });
         // 3000 is a naive value, we assume that after 3 seconds the system is ready
         // to start watching again. (Network interface/DNS is ready etc.)  
         }, 3000);