add option to configure a different installer stack

Author: oliviergaumond

reference-artifacts/Custom-Scripts/lza-upgrade/src/config.ts

@@ -36,4 +36,6 @@ export interface Config {
   skipDriftDetection?: boolean;
   localConfigFilePath?: string;
   enableTerminationProtection?: boolean;
+  lzaInstallerTemplateBucket?: string
+  lzaInstallerTemplateKey?: string
 }

reference-artifacts/Custom-Scripts/lza-upgrade/src/preparation.ts

@@ -55,7 +55,8 @@ export class Preparation {
   }
 
   async prepareLza() {
-    await getLZAInstallerStackTemplate('solutions-reference');
+    await getLZAInstallerStackTemplate(this.config.lzaInstallerTemplateBucket ?? 'solutions-reference',
+      this.config.lzaInstallerTemplateKey ?? 'landing-zone-accelerator-on-aws/latest/AWSAccelerator-InstallerStack.template');
     await putLZAInstallerStackTemplate(this.config.aseaConfigBucketName, this.homeRegion);
     const installerStackParameters: InstallerStackParameters = {
       repositorySource: this.config.lzaCodeRepositorySource ?? 'github',

reference-artifacts/Custom-Scripts/lza-upgrade/src/preparation/aws-lza.ts

@@ -147,12 +147,12 @@ export async function createLZAInstallerCloudFormationStack(
   }
 }
 
-export async function getLZAInstallerStackTemplate(bucketName: string) {
+export async function getLZAInstallerStackTemplate(bucketName: string, objectKey: string) {
   const s3Client = new S3Client({ endpoint: 'https://s3.amazonaws.com', region: 'us-east-1' });
   const template = await s3Client.send(
     new GetObjectCommand({
       Bucket: bucketName,
-      Key: 'landing-zone-accelerator-on-aws/latest/AWSAccelerator-InstallerStack.template',
+      Key: objectKey,
     }),
   );