[8.18] [UA] Use reindex_required metadata to drive corrective actions (#214532) (#214643)

# Backport

This will backport the following commits from `8.x` to `8.18`:
- [[UA] Use `reindex_required` metadata to drive corrective actions
(#214532)](https://github.com/elastic/kibana/pull/214532)

<!--- Backport version: 9.6.6 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sorenlouv/backport)

<!--BACKPORT [{"author":{"name":"Jean-Louis
Leysens","email":"jeanlouis.leysens@elastic.co"},"sourceCommit":{"committedDate":"2025-03-14T18:50:43Z","message":"[UA]
Use `reindex_required` metadata to drive corrective actions
(#214532)\n\n## Summary\n\nTested locally and critical old data
deprecations are still surfaced as\nexpected\n\n<img width=\"586\"
alt=\"Screenshot 2025-03-14 at 10 12
50\"\nsrc=\"https://github.com/user-attachments/assets/25d87fbd-7c98-45e0-a86a-d513ea455571\"\n/>","sha":"26aba9287821f289deb11b27079a9a7d0945c714","branchLabelMapping":{"^v8.16.0$":"main","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["Team:Core","release_note:skip","Feature:Upgrade
Assistant","backport:version","v8.18.0","v8.19.0","v8.18.1"],"title":"[UA]
Use `reindex_required` metadata to drive corrective
actions","number":214532,"url":"https://github.com/elastic/kibana/pull/214532","mergeCommit":{"message":"[UA]
Use `reindex_required` metadata to drive corrective actions
(#214532)\n\n## Summary\n\nTested locally and critical old data
deprecations are still surfaced as\nexpected\n\n<img width=\"586\"
alt=\"Screenshot 2025-03-14 at 10 12
50\"\nsrc=\"https://github.com/user-attachments/assets/25d87fbd-7c98-45e0-a86a-d513ea455571\"\n/>","sha":"26aba9287821f289deb11b27079a9a7d0945c714"}},"sourceBranch":"8.x","suggestedTargetBranches":["8.18"],"targetPullRequestStates":[{"branch":"8.18","label":"v8.18.0","branchLabelMappingKey":"^v(\\d+).(\\d+).\\d+$","isSourceBranch":false,"state":"NOT_CREATED"},{"branch":"8.19","label":"v8.19.0","branchLabelMappingKey":"^v(\\d+).(\\d+).\\d+$","isSourceBranch":false,"state":"NOT_CREATED"}]}]
BACKPORT-->

x-pack/platform/plugins/private/upgrade_assistant/server/lib/__fixtures__/fake_deprecations.json

@@ -69,7 +69,10 @@
         "message": "Index created before 7.0",
         "url": "https: //www.elastic.co/guide/en/elasticsearch/reference/master/breaking-changes-8.0.html",
         "details": "This index was created using version: 6.8.13",
-        "resolve_during_rolling_upgrade": false
+        "resolve_during_rolling_upgrade": false,
+        "_meta": {
+          "reindex_required": true
+        }
       }
     ],
     "frozen_index": [
@@ -97,7 +100,10 @@
         "message": "Index created before 7.0",
         "url": "https: //www.elastic.co/guide/en/elasticsearch/reference/master/breaking-changes-8.0.html",
         "details": "This index was created using version: 6.8.13",
-        "resolve_during_rolling_upgrade": false
+        "resolve_during_rolling_upgrade": false,
+        "_meta": {
+          "reindex_required": true
+        }
       }
     ],
     "deprecated_settings": [
@@ -183,7 +189,10 @@
         "message": "Old index with a compatibility version < 8.0",
         "url": "https://www.elastic.co/guide/en/elasticsearch/reference/master/breaking-changes-9.0.html",
         "details": "This index has version: 7.17.25",
-        "resolve_during_rolling_upgrade": false
+        "resolve_during_rolling_upgrade": false,
+        "_meta": {
+          "reindex_required": true
+        }
       }
     ],
     ".ent-search-1": [

x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/get_corrective_actions.ts

@@ -44,12 +44,6 @@ interface DataStreamActionMetadata extends CommonActionMetadata {
 
 export type EsMetadata = IndexActionMetadata | MlActionMetadata | DataStreamActionMetadata;
 
-// TODO(jloleysens): Replace these regexes once this issue is addressed https://github.com/elastic/elasticsearch/issues/118062
-const ES_INDEX_MESSAGES_REQUIRING_REINDEX = [
-  /Index created before/,
-  /index with a compatibility version \</,
-];
-
 export const isFrozenDeprecation = (message: string, indexName?: string): boolean =>
   Boolean(indexName) && message.includes(`Index [${indexName}] is a frozen index`);
 
@@ -62,9 +56,9 @@ export const getCorrectiveAction = (deprecation: BaseDeprecation): CorrectiveAct
   const clusterSettingDeprecation = metadata?.actions?.find(
     (action) => action.action_type === 'remove_settings' && typeof index === 'undefined'
   );
-  const requiresReindexAction = ES_INDEX_MESSAGES_REQUIRING_REINDEX.some((regexp) =>
-    regexp.test(message)
-  );
+  const requiresReindexAction =
+    (type === 'index_settings' || type === 'node_settings') &&
+    (deprecation.metadata as IndexActionMetadata)?.reindex_required === true;
   const requiresUnfreezeAction = isFrozenDeprecation(message, index);
   const requiresIndexSettingsAction = Boolean(indexSettingDeprecation);
   const requiresClusterSettingsAction = Boolean(clusterSettingDeprecation);

x-pack/platform/plugins/private/upgrade_assistant/server/lib/es_deprecations_status/index.test.ts

@@ -219,6 +219,9 @@ describe('getESUpgradeStatus', () => {
           details: 'This index was created using version: 6.8.13',
           // @ts-ignore
           resolve_during_rolling_upgrade: false,
+          _meta: {
+            reindex_required: true,
+          },
         },
         {
           level: 'critical',
@@ -227,6 +230,9 @@ describe('getESUpgradeStatus', () => {
           details: 'This index was created using version: 6.8.13',
           // @ts-ignore
           resolve_during_rolling_upgrade: false,
+          _meta: {
+            reindex_required: true,
+          },
         },
       ],
       ml_settings: [],
@@ -394,6 +400,9 @@ describe('getESUpgradeStatus', () => {
           details: 'This index was created using version: 6.8.13',
           // @ts-ignore
           resolve_during_rolling_upgrade: false,
+          _meta: {
+            reindex_required: true,
+          },
         },
       ],
       ml_settings: [],

x-pack/test/upgrade_assistant_integration/upgrade_assistant/api_deprecations.ts

@@ -207,7 +207,7 @@ export default function ({ getService }: FtrProviderContext) {
         );
       });
     });
-    it('GET /api/upgrade_assistant/status does not return { readyForUpgrade: false } if there are only critical API deprecations', async () => {
+    it('Readiness status excludes critical deprecations based on Kibana API usage', async () => {
       /** Throw in another critical deprecation... */
       await supertest.get(`/api/routing_example/d/removed_route`).expect(200);
       // sleep a little until the usage counter is synced into ES
@@ -224,7 +224,9 @@ export default function ({ getService }: FtrProviderContext) {
         2000
       );
       const { body } = await supertest.get(`/api/upgrade_assistant/status`).expect(200);
-      // There are critical deprecations, but we expect none of them to be related to Kibana
+
+      // There are critical deprecations for Kibana API usage, but we do not
+      // surface them in readiness status
       expect(body.readyForUpgrade).to.be(false);
       expect(body.details?.length > 0).to.be(true);
       expect(/Kibana/gi.test(body.details)).to.be(false);