Merge pull request #304 from rancher-sandbox/253c-handle-delays-reading-config

Be more careful when processing the config file:

Author: mattfarina

src/k8s-engine/k3sHelper.ts

@@ -453,6 +453,23 @@ export default class K3sHelper extends events.EventEmitter implements VersionLis
         await workFile.close();
       }
 
+      // On Windows repeat until the kubeconfig file is readable
+      let delay = 0; // msec
+      const delayIncrement = 200;
+      const maxDelay = 10_000;
+
+      while (delay < maxDelay) {
+        try {
+          await fs.promises.readFile(workPath, { encoding: 'utf-8' });
+          break;
+        } catch (err) {
+          console.log(`Error reading ${ workPath }: ${ err }`);
+          console.log(`Waiting for ${ delay / 1000.0 } sec`);
+          delay += delayIncrement;
+          await util.promisify(setTimeout)(delay);
+        }
+      }
+
       // For some reason, using KubeConfig.loadFromFile presents permissions
       // errors; doing the same ourselves seems to work better.  Since the file
       // comes from the WSL container, it must not contain any paths, so there

src/k8s-engine/wsl.ts

@@ -242,7 +242,7 @@ export default class WSLBackend extends events.EventEmitter implements K8s.Kuber
         }
       });
 
-      // Wait for k3s server; note that we're delibrately sending a HTTP request
+      // Wait for k3s server; note that we're deliberately sending an HTTP request
       // to an HTTPS server, and expecting an error response back.
       while (true) {
         try {
@@ -259,8 +259,13 @@ export default class WSLBackend extends events.EventEmitter implements K8s.Kuber
         await util.promisify(setTimeout)(500);
       }
 
-      await this.k3sHelper.updateKubeconfig(
-        'wsl.exe', '--distribution', 'k3s', '--exec', '/usr/local/bin/kubeconfig');
+      try {
+        await this.k3sHelper.updateKubeconfig(
+          'wsl.exe', '--distribution', 'k3s', '--exec', '/usr/local/bin/kubeconfig');
+      } catch (err) {
+        console.log(`k3sHelper.updateKubeconfig failed: ${ err }. Will retry...`);
+        throw err;
+      }
 
       this.client = new K8s.Client();
       await this.client.waitForServiceWatcher();

src/menu/tray.js

@@ -7,6 +7,7 @@ const { EventEmitter } = require('events');
 const fs = require('fs');
 const pth = require('path');
 const electron = require('electron');
+const yaml = require('yaml');
 const k8s = require('@kubernetes/client-node');
 const kubectl = require('../k8s-engine/kubectl.js');
 const kubeconfig = require('../config/kubeconfig.js');
@@ -83,17 +84,60 @@ export class Tray extends EventEmitter {
     if (!kubeconfigPath) {
       throw new Error('No kubeconfig path found');
     }
-    fs.watch(kubeconfigPath, () => {
-      this.updateContexts();
-      const contextMenu = electron.Menu.buildFromTemplate(this.#contextMenuItems);
+    this.buildFromConfig(kubeconfigPath);
+    const watcher = fs.watch(kubeconfigPath);
 
-      this.#trayMenu.setContextMenu(contextMenu);
+    watcher.on('error', (code, signal) => {
+      console.log(`Failed to fs.watch ${ kubeconfigPath }: code: ${ code }, signal: ${ signal }`);
+    });
+    watcher.on('change', (eventType, _) => {
+      if (eventType === 'rename' && !kubeconfig.hasAccess(kubeconfigPath)) {
+        // File doesn't exist. Wait for it to be recreated
+        return;
+      }
+      this.buildFromConfig(kubeconfigPath);
     });
 
     this.on('k8s-check-state', this.k8sStateChanged.bind(this));
     this.on('settings-update', this.settingsChanged.bind(this));
   }
 
+  buildFromConfig(configPath) {
+    if (!kubeconfig.hasAccess(configPath)) {
+      return;
+    }
+
+    try {
+      let parsedConfig;
+      const contents = fs.readFileSync(configPath).toString();
+
+      if (contents.length === 0) {
+        console.log('Config file is empty, will try to process it later');
+
+        return;
+      }
+
+      try {
+        parsedConfig = yaml.parse(contents);
+      } catch (err) {
+        console.log(`yaml parse failure: ${ err } on kubeconfig: contents ${ contents }., will retry later.`);
+        parsedConfig = null;
+      }
+
+      if ((parsedConfig?.clusters || []).length === 0) {
+        console.log('Config file has no clusters, will retry later');
+
+        return;
+      }
+      this.updateContexts();
+      const contextMenu = electron.Menu.buildFromTemplate(this.#contextMenuItems);
+
+      this.#trayMenu.setContextMenu(contextMenu);
+    } catch (err) {
+      console.log(`Error trying to update context menu: ${ err }`);
+    }
+  }
+
   /**
    * Called when the Kubernetes cluster state has changed.
    * @param {State} state The new cluster state.