chore: allow downloading a specific version of kubectl in tests

This is a prerequisite to adding OpenShift 3 tests, where we want to use a specific version of Kubernetes and of kubectl.

Author: ivanstanev

test/helpers/kubectl.ts

@@ -1,21 +1,29 @@
 import { exec } from 'child-process-promise';
-import { chmodSync, writeFileSync, existsSync } from 'fs';
+import { chmodSync, writeFileSync, existsSync, unlinkSync } from 'fs';
 import { platform } from 'os';
 import { resolve } from 'path';
 import * as needle from 'needle';
 import * as sleep from 'sleep-promise';
 
-export async function downloadKubectl(): Promise<void> {
+/**
+ * @param version For example: "v1.18.0"
+ */
+export async function downloadKubectl(version: string): Promise<void> {
   const kubectlPath = resolve(process.cwd(), 'kubectl');
   if (existsSync(kubectlPath)) {
-    return;
+    if (version === 'latest') {
+      return;
+    }
+
+    // Always start clean when requesting a specific version.
+    unlinkSync(kubectlPath);
   }
 
-  console.log('Downloading kubectl...');
+  console.log(`Downloading kubectl ${version}...`);
 
   // eslint-disable-next-line @typescript-eslint/camelcase
   const requestOptions = { follow_max: 2 };
-  const k8sRelease = await getLatestStableK8sRelease();
+  const k8sRelease = version === 'latest' ? await getLatestStableK8sRelease() : version;
   const osDistro = platform();
   const bodyData = null;
   await needle('get', 'https://storage.googleapis.com/kubernetes-release/release/' +

test/setup/index.ts

@@ -2,7 +2,7 @@ import * as fs from 'fs';
 import * as sleep from 'sleep-promise';
 import * as uuidv4 from 'uuid/v4';
 
-import platforms from './platforms';
+import platforms, { getKubernetesVersionForPlatform } from './platforms';
 import deployers from './deployers';
 import { IImageOptions } from './deployers/types';
 import * as kubectl from '../helpers/kubectl';
@@ -92,10 +92,12 @@ export async function deployMonitor(): Promise<string> {
 
     console.log(`platform chosen is ${testPlatform}, createCluster===${createCluster}`);
 
-    await kubectl.downloadKubectl();
+    const kubernetesVersion = getKubernetesVersionForPlatform(testPlatform);
+    await kubectl.downloadKubectl(kubernetesVersion);
+
     await platforms[testPlatform].setupTester();
     if (createCluster) {
-      await platforms[testPlatform].create();
+      await platforms[testPlatform].create(kubernetesVersion);
       await platforms[testPlatform].config();
     } else {
       await platforms[testPlatform].config();

test/setup/platforms/index.ts

@@ -4,7 +4,7 @@ import * as openshift4 from './openshift4';
 
 interface IPlatformSetup {
   // create a Kubernetes cluster
-  create: () => Promise<void>;
+  create: (version: string) => Promise<void>;
   // loads the image so Kubernetes may run it, return the name of the image in its registry's format
   loadImage: (imageNameAndTag: string) => Promise<string>;
   // delete a Kubernetes cluster
@@ -44,6 +44,10 @@ const openshift4Setup: IPlatformSetup = {
   setupTester: openshift4.setupTester,
 };
 
+export function getKubernetesVersionForPlatform(testPlatform: string): string {
+  return 'latest';
+}
+
 export default {
   kind: kindSetup,
   eks: eksSetup,

test/setup/platforms/kind.ts

@@ -11,9 +11,9 @@ export async function setupTester(): Promise<void> {
   await download(osDistro);
 }
 
-export async function createCluster(): Promise<void> {
+export async function createCluster(version: string): Promise<void> {
   // available tags may be viewed at https://hub.docker.com/r/kindest/node/tags
-  const kindImageTag = 'latest';
+  const kindImageTag = version;
   console.log(`Creating cluster "${clusterName}" with Kind image tag ${kindImageTag}...`);
 
   let kindImageArgument = '';

test/system/kind.test.ts

@@ -44,12 +44,13 @@ tap.test('Kubernetes-Monitor with KinD', async (t) => {
     process.env['PATH'] = process.env['PATH'] + ':./skopeo';
   }
 
+  const kubernetesVersion = 'latest';
   // kubectl
-  await kubectl.downloadKubectl();
+  await kubectl.downloadKubectl(kubernetesVersion);
 
   // KinD
   await kind.setupTester();
-  await kind.createCluster();
+  await kind.createCluster(kubernetesVersion);
   await kind.exportKubeConfig();
 
   await Promise.all([