[Fleet] Update experimental indexing features text + allow disabling TSDB (#149594)

## Summary

Closes #149591

Making some needed improvements/changes to our experimental data stream
features:
- Improve copy to better explain what these features are and what they
do
- Add explainer + link to
https://www.elastic.co/guide/en/elasticsearch/reference/master/use-a-data-stream.html#manually-roll-over-a-data-stream
for current need around manual rollovers
(#143448 coming soon for
automating this)


![image](https://user-images.githubusercontent.com/6766512/214857301-bb522d2a-f241-4c34-8bf5-bd96e610a139.png)

## Screen recording


https://user-images.githubusercontent.com/6766512/214861783-0efdbab9-51de-44f0-93ba-86011d6e9612.mov

---------

Co-authored-by: Kibana Machine <42973632+kibanamachine@users.noreply.github.com>

Author: kpollich

packages/kbn-doc-links/src/get_doc_links.ts

@@ -661,6 +661,7 @@ export const getDocLinks = ({ kibanaBranch }: GetDocLinkOptions): DocLinks => {
       datastreams: `${FLEET_DOCS}data-streams.html`,
       datastreamsILM: `${FLEET_DOCS}data-streams.html#data-streams-ilm`,
       datastreamsNamingScheme: `${FLEET_DOCS}data-streams.html#data-streams-naming-scheme`,
+      datastreamsManualRollover: `${ELASTICSEARCH_DOCS}use-a-data-stream.html#manually-roll-over-a-data-stream`,
       installElasticAgent: `${FLEET_DOCS}install-fleet-managed-elastic-agent.html`,
       installElasticAgentStandalone: `${FLEET_DOCS}install-standalone-elastic-agent.html`,
       upgradeElasticAgent: `${FLEET_DOCS}upgrade-elastic-agent.html`,

packages/kbn-doc-links/src/types.ts

@@ -433,6 +433,7 @@ export interface DocLinks {
     datastreams: string;
     datastreamsILM: string;
     datastreamsNamingScheme: string;
+    datastreamsManualRollover: string;
     installElasticAgent: string;
     installElasticAgentStandalone: string;
     packageSignatures: string;

x-pack/plugins/fleet/public/applications/fleet/sections/agent_policy/create_package_policy_page/components/steps/components/experimental_datastream_settings.test.tsx

@@ -178,14 +178,91 @@ describe('ExperimentDatastreamSettings', () => {
           },
         },
       ]);
-      expect(experimentalDataFeatures).toEqual([
+    });
+  });
+  describe('TSDB', () => {
+    it('should be enabled and unchecked by default', () => {
+      const mockSetNewExperimentalDataFeatures = jest.fn();
+      const res = createFleetTestRendererMock().render(
+        <ExperimentDatastreamSettings
+          registryDataStream={{ type: 'logs', dataset: 'test' } as unknown as RegistryDataStream}
+          experimentalDataFeatures={[]}
+          setNewExperimentalDataFeatures={mockSetNewExperimentalDataFeatures}
+        />
+      );
+
+      const tsdbSwitch = res.getByTestId('packagePolicyEditor.tsdbExperimentalFeature.switch');
+
+      expect(tsdbSwitch).toBeEnabled();
+      expect(tsdbSwitch).not.toBeChecked();
+      expect(mockSetNewExperimentalDataFeatures).not.toBeCalled();
+    });
+
+    it('should be enabled and checked if registry data streams includes "elasticsearch.index_mode: time_series"', () => {
+      const mockSetNewExperimentalDataFeatures = jest.fn();
+      const res = createFleetTestRendererMock().render(
+        <ExperimentDatastreamSettings
+          registryDataStream={
+            {
+              type: 'logs',
+              dataset: 'test',
+              elasticsearch: {
+                index_mode: 'time_series',
+              },
+            } as unknown as RegistryDataStream
+          }
+          experimentalDataFeatures={[]}
+          setNewExperimentalDataFeatures={mockSetNewExperimentalDataFeatures}
+        />
+      );
+
+      const tsdbSwitch = res.getByTestId('packagePolicyEditor.tsdbExperimentalFeature.switch');
+
+      expect(tsdbSwitch).toBeEnabled();
+      expect(tsdbSwitch).toBeChecked();
+      expect(mockSetNewExperimentalDataFeatures).not.toBeCalled();
+    });
+
+    it('should not mutate other experimental features when changed', () => {
+      const experimentalDataFeatures = [
         {
           data_stream: 'logs-test',
           features: {
+            doc_value_only_numeric: false,
+            doc_value_only_other: false,
             synthetic_source: true,
             tsdb: false,
+          },
+        },
+      ];
+
+      const mockSetNewExperimentalDataFeatures = jest.fn();
+      const res = createFleetTestRendererMock().render(
+        <ExperimentDatastreamSettings
+          registryDataStream={
+            {
+              type: 'logs',
+              dataset: 'test',
+            } as unknown as RegistryDataStream
+          }
+          experimentalDataFeatures={experimentalDataFeatures}
+          setNewExperimentalDataFeatures={mockSetNewExperimentalDataFeatures}
+        />
+      );
+
+      act(() => {
+        fireEvent.click(res.getByTestId('packagePolicyEditor.tsdbExperimentalFeature.switch'));
+      });
+
+      expect(mockSetNewExperimentalDataFeatures).toBeCalled();
+      expect(mockSetNewExperimentalDataFeatures.mock.calls[0][0]).toEqual([
+        {
+          data_stream: 'logs-test',
+          features: {
             doc_value_only_numeric: false,
             doc_value_only_other: false,
+            synthetic_source: true,
+            tsdb: true,
           },
         },
       ]);

x-pack/plugins/fleet/public/applications/fleet/sections/agent_policy/create_package_policy_page/components/steps/components/experimental_datastream_settings.tsx

@@ -15,8 +15,11 @@ import {
   EuiText,
   EuiSpacer,
   EuiTitle,
-  EuiToolTip,
+  EuiLink,
 } from '@elastic/eui';
+import { i18n } from '@kbn/i18n';
+
+import { useStartServices } from '../../../../../../../../hooks';
 
 import type {
   ExperimentalDataStreamFeature,
@@ -50,6 +53,8 @@ export const ExperimentDatastreamSettings: React.FunctionComponent<Props> = ({
   experimentalDataFeatures,
   setNewExperimentalDataFeatures,
 }) => {
+  const { docLinks } = useStartServices();
+
   const isSyntheticSourceEditable = registryDataStream.elasticsearch?.source_mode !== 'default';
 
   const syntheticSourceExperimentalValue = getExperimentalFeatureValue(
@@ -129,27 +134,35 @@ export const ExperimentDatastreamSettings: React.FunctionComponent<Props> = ({
             <h5>
               <FormattedMessage
                 id="xpack.fleet.packagePolicyEditor.experimentalSettings.title"
-                defaultMessage="Indexing settings (experimental)"
+                defaultMessage="Indexing settings (technical preview)"
               />
             </h5>
           </EuiTitle>
         </EuiFlexItem>
         <EuiFlexItem>
           <EuiText color="subdued" size="xs">
-            <FormattedMessage
-              id="xpack.fleet.packagePolicyEditor.stepConfigure.experimentalFeaturesDescription"
-              defaultMessage="Select data streams to configure indexing options. This is an {experimentalFeature} and may have effects on other properties."
-              values={{
-                experimentalFeature: (
-                  <strong>
-                    <FormattedMessage
-                      id="xpack.fleet.packagePolicyEditor.experimentalFeatureText"
-                      defaultMessage="experimental feature"
-                    />
-                  </strong>
-                ),
-              }}
-            />
+            <p>
+              <FormattedMessage
+                id="xpack.fleet.packagePolicyEditor.stepConfigure.experimentalFeaturesDescription"
+                defaultMessage="Choose how you want to store backing indices for this data stream. Changing these settings may affect other properties."
+              />
+            </p>
+            <p>
+              <FormattedMessage
+                id="xpack.fleet.packagePolicyEditor.stepConfigure.experimentalFeaturesRolloverWarning"
+                defaultMessage="After changing these settings, you need to manually roll over the existing data stream for changes to take effect. {learnMoreLink}"
+                values={{
+                  learnMoreLink: (
+                    <EuiLink href={docLinks.links.fleet.datastreamsManualRollover} target="_blank">
+                      {i18n.translate(
+                        'xpack.fleet.packagePolicyEditor.experimentalFeatureRolloverLearnMore',
+                        { defaultMessage: 'Learn more' }
+                      )}
+                    </EuiLink>
+                  ),
+                }}
+              />
+            </p>
           </EuiText>
         </EuiFlexItem>
         <EuiSpacer size="s" />
@@ -172,31 +185,21 @@ export const ExperimentDatastreamSettings: React.FunctionComponent<Props> = ({
           />
         </EuiFlexItem>
         <EuiFlexItem>
-          <EuiToolTip
-            content={
+          <EuiSwitch
+            checked={newExperimentalIndexingFeature.tsdb ?? false}
+            data-test-subj="packagePolicyEditor.tsdbExperimentalFeature.switch"
+            label={
               <FormattedMessage
-                id="xpack.fleet.packagePolicyEditor.experimentalFeatures.TSDBTooltip"
-                defaultMessage="Enabling this feature is irreversible"
+                id="xpack.fleet.packagePolicyEditor.experimentalFeatures.TSDBLabel"
+                defaultMessage="Time-series indexing (TSDB)"
               />
             }
-          >
-            <EuiSwitch
-              disabled={newExperimentalIndexingFeature.tsdb ?? false}
-              checked={newExperimentalIndexingFeature.tsdb ?? false}
-              data-test-subj="packagePolicyEditor.tsdbExperimentalFeature.switch"
-              label={
-                <FormattedMessage
-                  id="xpack.fleet.packagePolicyEditor.experimentalFeatures.TSDBLabel"
-                  defaultMessage="Time-series indexing (TSDB)"
-                />
-              }
-              onChange={(e) => {
-                onIndexingSettingChange({
-                  tsdb: e.target.checked,
-                });
-              }}
-            />
-          </EuiToolTip>
+            onChange={(e) => {
+              onIndexingSettingChange({
+                tsdb: e.target.checked,
+              });
+            }}
+          />
         </EuiFlexItem>
         <EuiFlexItem>
           <EuiSwitch

x-pack/plugins/fleet/server/services/package_policies/experimental_datastream_features.ts

@@ -152,7 +152,7 @@ export async function handleExperimentalDatastreamFeatureOptIn({
       });
     }
 
-    if (isTSDBOptInChanged && featureMapEntry.features.tsdb) {
+    if (isTSDBOptInChanged) {
       const indexTemplateRes = await esClient.indices.getIndexTemplate({
         name: featureMapEntry.data_stream,
       });
@@ -165,14 +165,15 @@ export async function handleExperimentalDatastreamFeatureOptIn({
           settings: {
             ...(indexTemplate.template?.settings ?? {}),
             index: {
-              mode: 'time_series',
+              mode: featureMapEntry.features.tsdb ? 'time_series' : null,
             },
           },
         },
       };
 
       await esClient.indices.putIndexTemplate({
         name: featureMapEntry.data_stream,
+        // @ts-expect-error
         body: indexTemplateBody,
       });
     }