[Upgrade Assistant] Update copy around system indices (#123946) (#124032) (#124129)

(cherry picked from commit 58d54b2ad4)

src/core/public/doc_links/doc_links_service.ts

@@ -231,6 +231,7 @@ export class DocLinksService {
           asyncSearch: `${ELASTICSEARCH_DOCS}async-search-intro.html`,
           dataStreams: `${ELASTICSEARCH_DOCS}data-streams.html`,
           deprecationLogging: `${ELASTICSEARCH_DOCS}logging.html#deprecation-logging`,
+          hiddenIndices: `${ELASTICSEARCH_DOCS}multi-index.html#hidden`,
           ilm: `${ELASTICSEARCH_DOCS}index-lifecycle-management.html`,
           ilmForceMerge: `${ELASTICSEARCH_DOCS}ilm-forcemerge.html`,
           ilmFreeze: `${ELASTICSEARCH_DOCS}ilm-freeze.html`,

x-pack/plugins/translations/translations/ja-JP.json

@@ -27576,7 +27576,6 @@
     "xpack.upgradeAssistant.overview.pageDescription": "次のバージョンのElasticをお待ちください。",
     "xpack.upgradeAssistant.overview.pageTitle": "アップグレードアシスタント",
     "xpack.upgradeAssistant.overview.snapshotRestoreLink": "スナップショットの作成",
-    "xpack.upgradeAssistant.overview.systemIndices.body": "アップグレード前に、システム情報が格納されたインデックスを移行します。",
     "xpack.upgradeAssistant.overview.systemIndices.errorLabel": "移行失敗",
     "xpack.upgradeAssistant.overview.systemIndices.featureNameTableColumn": "機能",
     "xpack.upgradeAssistant.overview.systemIndices.flyoutCloseButtonLabel": "閉じる",

x-pack/plugins/translations/translations/zh-CN.json

@@ -28048,7 +28048,6 @@
     "xpack.upgradeAssistant.overview.pageDescription": "准备使用下一版 Elastic！",
     "xpack.upgradeAssistant.overview.pageTitle": "升级助手",
     "xpack.upgradeAssistant.overview.snapshotRestoreLink": "创建快照",
-    "xpack.upgradeAssistant.overview.systemIndices.body": "在升级之前迁移存储系统信息的索引。",
     "xpack.upgradeAssistant.overview.systemIndices.errorLabel": "迁移失败",
     "xpack.upgradeAssistant.overview.systemIndices.featureNameTableColumn": "功能",
     "xpack.upgradeAssistant.overview.systemIndices.flyoutCloseButtonLabel": "关闭",

x-pack/plugins/upgrade_assistant/public/application/components/es_deprecations/es_deprecations.tsx

@@ -46,7 +46,7 @@ const i18nTexts = {
   }),
   pageDescription: i18n.translate('xpack.upgradeAssistant.esDeprecations.pageDescription', {
     defaultMessage:
-      'Resolve all critical issues before upgrading. Before making changes, ensure you have a current snapshot of your cluster. Indices created before 7.0 must be reindexed or removed.',
+      'Resolve all critical issues before upgrading. Before making changes, ensure you have a current snapshot of your cluster. Indices created before 7.0 must be reindexed or removed, including hidden indices such as those used to store Machine Learning data.',
   }),
   isLoading: i18n.translate('xpack.upgradeAssistant.esDeprecations.loadingText', {
     defaultMessage: 'Loading deprecation issues…',

x-pack/plugins/upgrade_assistant/public/application/components/overview/migrate_system_indices/migrate_system_indices.tsx

@@ -19,9 +19,11 @@ import {
   EuiFlexGroup,
   EuiFlexItem,
   EuiCode,
+  EuiLink,
 } from '@elastic/eui';
 import type { EuiStepProps } from '@elastic/eui/src/components/steps/step';
 
+import { DocLinksStart } from 'kibana/public';
 import type { SystemIndicesMigrationFeature } from '../../../../../common/types';
 import type { OverviewStepProps } from '../../types';
 import { useMigrateSystemIndices } from './use_migrate_system_indices';
@@ -48,9 +50,24 @@ const i18nTexts = {
   title: i18n.translate('xpack.upgradeAssistant.overview.systemIndices.title', {
     defaultMessage: 'Migrate system indices',
   }),
-  bodyDescription: i18n.translate('xpack.upgradeAssistant.overview.systemIndices.body', {
-    defaultMessage: 'Migrate the indices that store system information before you upgrade.',
-  }),
+  bodyDescription: (docLink: string) => {
+    return (
+      <FormattedMessage
+        id="xpack.upgradeAssistant.overview.systemIndices.body"
+        defaultMessage="Prepare the system indices that store internal information for the upgrade. Any {hiddenIndicesLink} that need to be reindexed are shown in the next step."
+        values={{
+          hiddenIndicesLink: (
+            <EuiLink external target="_blank" href={docLink}>
+              <FormattedMessage
+                id="xpack.upgradeAssistant.overview.systemIndices.body.hiddenIndicesLink"
+                defaultMessage="hidden indices"
+              />
+            </EuiLink>
+          ),
+        }}
+      />
+    );
+  },
   startButtonLabel: i18n.translate(
     'xpack.upgradeAssistant.overview.systemIndices.startButtonLabel',
     {
@@ -214,10 +231,15 @@ const MigrateSystemIndicesStep: FunctionComponent<Props> = ({ setIsComplete }) =
   );
 };
 
+interface CustomProps {
+  docLinks: DocLinksStart;
+}
+
 export const getMigrateSystemIndicesStep = ({
   isComplete,
   setIsComplete,
-}: OverviewStepProps): EuiStepProps => {
+  docLinks,
+}: OverviewStepProps & CustomProps): EuiStepProps => {
   const status = isComplete ? 'complete' : 'incomplete';
 
   return {
@@ -227,7 +249,7 @@ export const getMigrateSystemIndicesStep = ({
     children: (
       <>
         <EuiText>
-          <p>{i18nTexts.bodyDescription}</p>
+          <p>{i18nTexts.bodyDescription(docLinks.links.elasticsearch.hiddenIndices)}</p>
         </EuiText>
 
         <EuiSpacer size="m" />

x-pack/plugins/upgrade_assistant/public/application/components/overview/overview.tsx

@@ -107,6 +107,7 @@ export const Overview = withRouter(({ history }: RouteComponentProps) => {
               setIsComplete: setCompletedStep.bind(null, 'backup'),
             }),
             getMigrateSystemIndicesStep({
+              docLinks,
               isComplete: isStepComplete('migrate_system_indices'),
               setIsComplete: setCompletedStep.bind(null, 'migrate_system_indices'),
             }),