[ES Query] Fix saving ECS group by fields for query DSL rule (#203769)

Fixes #203472

## Summary

|Rule|Group info|
|---|---|

|![image](https://github.com/user-attachments/assets/fc17c630-d7c2-4615-8056-5e04209b71e6)|![image](https://github.com/user-attachments/assets/55328973-d585-4148-a74f-d2c275b9989d)|

@elastic/response-ops What sort of test do you suggest to add for this
case?

### 🧪 How to run test

#### Deployment agnostic
- [x] Test on MKI
```
// Server
node scripts/functional_tests_server --config x-pack/test/api_integration/deployment_agnostic/configs/serverless/oblt.serverless.config.ts

// Test
node scripts/functional_test_runner --config=x-pack/test/api_integration/deployment_agnostic/configs/serverless/oblt.serverless.config.ts --grep="ElasticSearch query rule"
```

x-pack/plugins/stack_alerts/server/rule_types/es_query/lib/fetch_es_query.ts

@@ -154,6 +154,7 @@ export async function fetchEsQuery({
       esResult: searchResult,
       resultLimit: alertLimit,
       sourceFieldsParams: params.sourceFields,
+      termField: params.termField,
     }),
     link,
     index: params.index,

x-pack/test/alerting_api_integration/spaces_only/tests/alerting/group3/builtin_alert_types/es_query/query_dsl_only.ts

@@ -33,7 +33,7 @@ export default function ruleTests({ getService }: FtrProviderContext) {
   const { es, esTestIndexTool, esTestIndexToolOutput, createEsDocumentsInGroups, waitForDocs } =
     getRuleServices(getService);
 
-  describe('rule', () => {
+  describe('Query DSL only', () => {
     let endDate: string;
     let connectorId: string;
     const objectRemover = new ObjectRemover(supertest);

x-pack/test/api_integration/deployment_agnostic/apis/observability/alerting/es_query/index.ts

@@ -0,0 +1,15 @@
+/*
+ * 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 { DeploymentAgnosticFtrProviderContext } from '../../../../ftr_provider_context';
+
+export default function ({ loadTestFile }: DeploymentAgnosticFtrProviderContext) {
+  describe('ElasticSearch query rule', () => {
+    loadTestFile(require.resolve('./query_dsl'));
+    loadTestFile(require.resolve('./query_dsl_with_group_by'));
+  });
+}

x-pack/test/api_integration/deployment_agnostic/apis/observability/alerting/es_query_rule.ts → x-pack/test/api_integration/deployment_agnostic/apis/observability/alerting/es_query/query_dsl.ts

@@ -7,7 +7,7 @@
 
 import expect from '@kbn/expect';
 import { RoleCredentials, InternalRequestHeader } from '@kbn/ftr-common-functional-services';
-import { DeploymentAgnosticFtrProviderContext } from '../../../ftr_provider_context';
+import { DeploymentAgnosticFtrProviderContext } from '../../../../ftr_provider_context';
 
 export default function ({ getService }: DeploymentAgnosticFtrProviderContext) {
   const esClient = getService('es');
@@ -22,7 +22,7 @@ export default function ({ getService }: DeploymentAgnosticFtrProviderContext) {
   let adminRoleAuthc: RoleCredentials;
   let internalReqHeader: InternalRequestHeader;
 
-  describe('ElasticSearch query rule', () => {
+  describe('Query DSL', () => {
     const RULE_TYPE_ID = '.es-query';
     const ALERT_ACTION_INDEX = 'alert-action-es-query';
     const RULE_ALERT_INDEX = '.alerts-stack.alerts-default';

x-pack/test/api_integration/deployment_agnostic/apis/observability/alerting/es_query/query_dsl_with_group_by.ts

@@ -0,0 +1,207 @@
+/*
+ * 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 { cleanup, generate, Dataset, PartialConfig } from '@kbn/data-forge';
+import { RoleCredentials, InternalRequestHeader } from '@kbn/ftr-common-functional-services';
+import { DeploymentAgnosticFtrProviderContext } from '../../../../ftr_provider_context';
+import { ActionDocument } from './types';
+
+export default function ({ getService }: DeploymentAgnosticFtrProviderContext) {
+  const esClient = getService('es');
+  const logger = getService('log');
+  const samlAuth = getService('samlAuth');
+  const supertestWithoutAuth = getService('supertestWithoutAuth');
+  const esDeleteAllIndices = getService('esDeleteAllIndices');
+  const alertingApi = getService('alertingApi');
+  const config = getService('config');
+  const isServerless = config.get('serverless');
+  const expectedConsumer = isServerless ? 'observability' : 'logs';
+
+  let adminRoleAuthc: RoleCredentials;
+  let internalReqHeader: InternalRequestHeader;
+
+  describe('Query DQL with group by field', () => {
+    const RULE_TYPE_ID = '.es-query';
+    const ALERT_ACTION_INDEX = 'alert-action-es-query';
+    const RULE_ALERT_INDEX = '.alerts-stack.alerts-default';
+    const INDEX = 'kbn-data-forge-fake_hosts.fake_hosts-*';
+    let dataForgeConfig: PartialConfig;
+    let dataForgeIndices: string[];
+    let actionId: string;
+    let ruleId: string;
+
+    before(async () => {
+      adminRoleAuthc = await samlAuth.createM2mApiKeyWithRoleScope('admin');
+      internalReqHeader = samlAuth.getInternalRequestHeader();
+      dataForgeConfig = {
+        schedule: [
+          {
+            template: 'good',
+            start: 'now-10m',
+            end: 'now+5m',
+            metrics: [
+              { name: 'system.cpu.user.pct', method: 'linear', start: 2.5, end: 2.5 },
+              { name: 'system.cpu.total.pct', method: 'linear', start: 0.5, end: 0.5 },
+              { name: 'system.cpu.total.norm.pct', method: 'linear', start: 0.8, end: 0.8 },
+            ],
+          },
+        ],
+        indexing: {
+          dataset: 'fake_hosts' as Dataset,
+          eventsPerCycle: 1,
+          interval: 60000,
+          alignEventsToInterval: true,
+        },
+      };
+      dataForgeIndices = await generate({ client: esClient, config: dataForgeConfig, logger });
+      await alertingApi.waitForDocumentInIndex({
+        indexName: dataForgeIndices.join(','),
+        docCountTarget: 45,
+      });
+    });
+
+    after(async () => {
+      await supertestWithoutAuth
+        .delete(`/api/alerting/rule/${ruleId}`)
+        .set(adminRoleAuthc.apiKeyHeader)
+        .set(internalReqHeader);
+      await supertestWithoutAuth
+        .delete(`/api/actions/connector/${actionId}`)
+        .set(adminRoleAuthc.apiKeyHeader)
+        .set(internalReqHeader);
+      await esClient.deleteByQuery({
+        index: RULE_ALERT_INDEX,
+        query: { term: { 'kibana.alert.rule.uuid': ruleId } },
+        conflicts: 'proceed',
+      });
+      await esClient.deleteByQuery({
+        index: '.kibana-event-log-*',
+        query: { term: { 'rule.id': ruleId } },
+        conflicts: 'proceed',
+      });
+      await esDeleteAllIndices([ALERT_ACTION_INDEX, ...dataForgeIndices]);
+      await cleanup({ client: esClient, config: dataForgeConfig, logger });
+      await samlAuth.invalidateM2mApiKeyWithRoleScope(adminRoleAuthc);
+    });
+
+    describe('Rule creation', () => {
+      it('creates rule successfully', async () => {
+        actionId = await alertingApi.createIndexConnector({
+          roleAuthc: adminRoleAuthc,
+          name: 'Index Connector: Alerting API test',
+          indexName: ALERT_ACTION_INDEX,
+        });
+
+        const createdRule = await alertingApi.helpers.createEsQueryRule({
+          roleAuthc: adminRoleAuthc,
+          consumer: expectedConsumer,
+          name: 'always fire',
+          ruleTypeId: RULE_TYPE_ID,
+          params: {
+            size: 100,
+            thresholdComparator: '>',
+            threshold: [1],
+            index: [INDEX],
+            timeField: '@timestamp',
+            esQuery: `{\n  \"query\":{\n    \"match_all\" : {}\n  }\n}`,
+            timeWindowSize: 1,
+            timeWindowUnit: 'm',
+            groupBy: 'top',
+            termField: 'host.name',
+            termSize: 1,
+          },
+          actions: [
+            {
+              group: 'query matched',
+              id: actionId,
+              params: {
+                documents: [
+                  {
+                    ruleId: '{{rule.id}}',
+                    ruleName: '{{rule.name}}',
+                    ruleParams: '{{rule.params}}',
+                    spaceId: '{{rule.spaceId}}',
+                    tags: '{{rule.tags}}',
+                    alertId: '{{alert.id}}',
+                    alertActionGroup: '{{alert.actionGroup}}',
+                    instanceContextValue: '{{context.instanceContextValue}}',
+                    instanceStateValue: '{{state.instanceStateValue}}',
+                  },
+                ],
+              },
+              frequency: {
+                notify_when: 'onActiveAlert',
+                throttle: null,
+                summary: false,
+              },
+            },
+          ],
+        });
+        ruleId = createdRule.id;
+        expect(ruleId).not.to.be(undefined);
+      });
+
+      it('should be active', async () => {
+        const executionStatus = await alertingApi.waitForRuleStatus({
+          roleAuthc: adminRoleAuthc,
+          ruleId,
+          expectedStatus: 'active',
+        });
+        expect(executionStatus).to.be('active');
+      });
+
+      it('should find the created rule with correct information about the consumer', async () => {
+        const match = await alertingApi.findInRules(adminRoleAuthc, ruleId);
+        expect(match).not.to.be(undefined);
+        expect(match.consumer).to.be(expectedConsumer);
+      });
+
+      it('should set correct information in the alert document', async () => {
+        const resp = await alertingApi.waitForAlertInIndex({
+          indexName: RULE_ALERT_INDEX,
+          ruleId,
+        });
+
+        expect(resp.hits.hits[0]._source).property('host.name', 'host-0');
+        expect(resp.hits.hits[0]._source).property('kibana.alert.rule.consumer', expectedConsumer);
+        expect(resp.hits.hits[0]._source).property(
+          'kibana.alert.reason',
+          'Document count is 3 in the last 1m for host-0 in kbn-data-forge-fake_hosts.fake_hosts-* index. Alert when greater than 1.'
+        );
+        expect(resp.hits.hits[0]._source).property(
+          'kibana.alert.evaluation.conditions',
+          'Number of matching documents for group "host-0" is greater than 1'
+        );
+        expect(resp.hits.hits[0]._source).property('kibana.alert.evaluation.value', '3');
+        expect(resp.hits.hits[0]._source).property('kibana.alert.evaluation.threshold', 1);
+        expect(resp.hits.hits[0]._source).property('kibana.alert.rule.name', 'always fire');
+        expect(resp.hits.hits[0]._source).property('event.action', 'open');
+        expect(resp.hits.hits[0]._source).property('kibana.alert.action_group', 'query matched');
+        expect(resp.hits.hits[0]._source).property('kibana.alert.status', 'active');
+        expect(resp.hits.hits[0]._source).property('kibana.alert.workflow_status', 'open');
+        expect(resp.hits.hits[0]._source).property(
+          'kibana.alert.rule.category',
+          'Elasticsearch query'
+        );
+      });
+
+      it('should set correct action variables', async () => {
+        const resp = await alertingApi.waitForDocumentInIndex<ActionDocument>({
+          indexName: ALERT_ACTION_INDEX,
+        });
+
+        expect(resp.hits.hits[0]._source?.ruleId).eql(ruleId);
+        expect(resp.hits.hits[0]._source?.ruleName).eql('always fire');
+        expect(resp.hits.hits[0]._source?.ruleParams).eql(
+          '{"size":100,"thresholdComparator":">","threshold":[1],"index":["kbn-data-forge-fake_hosts.fake_hosts-*"],"timeField":"@timestamp","esQuery":"{\\n  \\"query\\":{\\n    \\"match_all\\" : {}\\n  }\\n}","timeWindowSize":1,"timeWindowUnit":"m","groupBy":"top","termField":"host.name","termSize":1,"excludeHitsFromPreviousRun":true,"aggType":"count","searchType":"esQuery"}'
+        );
+        expect(resp.hits.hits[0]._source?.alertActionGroup).eql('query matched');
+      });
+    });
+  });
+}

x-pack/test/api_integration/deployment_agnostic/apis/observability/alerting/es_query/types.ts

@@ -0,0 +1,16 @@
+/*
+ * 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.
+ */
+
+export interface ActionDocument {
+  ruleId: string;
+  ruleName: string;
+  ruleParams: string;
+  spaceId: string;
+  tags: string;
+  alertId: string;
+  alertActionGroup: string;
+}

x-pack/test/api_integration/deployment_agnostic/apis/observability/alerting/index.ts

@@ -10,7 +10,7 @@ import { DeploymentAgnosticFtrProviderContext } from '../../../ftr_provider_cont
 export default function ({ loadTestFile }: DeploymentAgnosticFtrProviderContext) {
   describe('Observability Alerting', () => {
     loadTestFile(require.resolve('./burn_rate_rule'));
-    loadTestFile(require.resolve('./es_query_rule'));
+    loadTestFile(require.resolve('./es_query'));
     loadTestFile(require.resolve('./custom_threshold'));
   });
 }