[Fleet] fix for upgrade package with tsds removed (elastic#157395)

## Summary

Fixes elastic#157345

To test:

Install `nginx-1.12.0-beta` which has `index.mode:time_series`.

```
POST http://elastic:changeme@localhost:5601/api/fleet/epm/packages/nginx-1.12.0-beta
kbn-xsrf: kibana

{
   "force": true
 }
```

Upgrade to `nginx-1.12.1-beta` which has `index.mode:time_series`
removed.

Upload this package built manually:

[nginx-1.12.1-beta.zip](https://github.com/elastic/kibana/files/11452945/nginx-1.12.1-beta.zip)

```
curl -XPOST -H 'content-type: application/zip' -H 'kbn-xsrf: true' http://localhost:5601/api/fleet/epm/packages -u elastic:changeme --data-binary @nginx-1.12.1-beta.zip
```

The package should install successfully and time_series should be
removed from the index template `metrics-nginx.stubstatus`

WIP: update tests

### Checklist

- [x] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios

(cherry picked from commit a0ee7b6)

x-pack/plugins/fleet/server/services/epm/elasticsearch/template/install.ts

@@ -219,10 +219,46 @@ export async function installComponentAndIndexTemplateForDataStream({
   componentTemplates: TemplateMap;
   indexTemplate: IndexTemplateEntry;
 }) {
+  // update index template first in case TSDS was removed, so that it does not become invalid
+  await updateIndexTemplateIfTsdsDisabled({ esClient, logger, indexTemplate });
+
   await installDataStreamComponentTemplates({ esClient, logger, componentTemplates });
   await installTemplate({ esClient, logger, template: indexTemplate });
 }
 
+async function updateIndexTemplateIfTsdsDisabled({
+  esClient,
+  logger,
+  indexTemplate,
+}: {
+  esClient: ElasticsearchClient;
+  logger: Logger;
+  indexTemplate: IndexTemplateEntry;
+}) {
+  try {
+    const existingIndexTemplate = await esClient.indices.getIndexTemplate({
+      name: indexTemplate.templateName,
+    });
+    if (
+      existingIndexTemplate.index_templates?.[0]?.index_template.template?.settings?.index?.mode ===
+        'time_series' &&
+      indexTemplate.indexTemplate.template.settings.index.mode !== 'time_series'
+    ) {
+      await installTemplate({ esClient, logger, template: indexTemplate });
+    }
+  } catch (e) {
+    if (e.statusCode === 404) {
+      logger.debug(
+        `Index template ${indexTemplate.templateName} does not exist, skipping time_series check`
+      );
+    } else {
+      logger.warn(
+        `Error while trying to install index template before component template: ${e.message}`
+      );
+    }
+  }
+}
+
 function putComponentTemplate(
   esClient: ElasticsearchClient,
   logger: Logger,

x-pack/test/fleet_api_integration/apis/epm/index.js

@@ -28,6 +28,7 @@ export default function loadTests({ loadTestFile, getService }) {
     loadTestFile(require.resolve('./install_remove_kbn_assets_in_space'));
     loadTestFile(require.resolve('./install_remove_multiple'));
     loadTestFile(require.resolve('./install_update'));
+    loadTestFile(require.resolve('./install_tsds_disable'));
     loadTestFile(require.resolve('./install_tag_assets'));
     loadTestFile(require.resolve('./bulk_upgrade'));
     loadTestFile(require.resolve('./update_assets'));

x-pack/test/fleet_api_integration/apis/epm/install_tsds_disable.ts

@@ -0,0 +1,63 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import expect from '@kbn/expect';
+import { FtrProviderContext } from '../../../api_integration/ftr_provider_context';
+import { skipIfNoDockerRegistry } from '../../helpers';
+import { setupFleetAndAgents } from '../agents/services';
+
+export default function (providerContext: FtrProviderContext) {
+  const { getService } = providerContext;
+  const supertest = getService('supertest');
+  const es = getService('es');
+
+  const deletePackage = async (name: string, version: string) => {
+    await supertest.delete(`/api/fleet/epm/packages/${name}/${version}`).set('kbn-xsrf', 'xxxx');
+  };
+
+  describe('installing with tsds disabled', async () => {
+    skipIfNoDockerRegistry(providerContext);
+    setupFleetAndAgents(providerContext);
+
+    after(async () => {
+      await deletePackage('nginx', '1.12.1-beta');
+    });
+
+    it('should upgrade with tsds disabled if nginx exists with tsds', async function () {
+      const templateName = 'metrics-nginx.stubstatus';
+
+      await supertest
+        .post(`/api/fleet/epm/packages/nginx/1.12.0-beta`)
+        .set('kbn-xsrf', 'xxxx')
+        .send({ force: true })
+        .expect(200);
+
+      expect(await getIndexMode(templateName)).to.eql('time_series');
+
+      await supertest
+        .post(`/api/fleet/epm/packages/nginx/1.12.1-beta`)
+        .set('kbn-xsrf', 'xxxx')
+        .send({ force: true })
+        .expect(200);
+
+      expect(await getIndexMode(templateName)).to.be(undefined);
+    });
+
+    async function getIndexMode(templateName: string) {
+      const { body: indexTemplateResponse } = await es.transport.request<any>(
+        {
+          method: 'GET',
+          path: `/_index_template/${templateName}`,
+        },
+        { meta: true }
+      );
+
+      const indexTemplate = indexTemplateResponse.index_templates[0].index_template;
+      return indexTemplate.template.settings.index?.mode;
+    }
+  });
+}