[Dataset Quality] Utility function to extract index name from backing… (

#183054)

closes #183052

## 📓 Summary


Created a utility function to extract index name from a given backing
index string.

x-pack/plugins/observability_solution/dataset_quality/common/utils/dataset_name.test.ts

@@ -9,6 +9,7 @@ import {
   dataStreamPartsToIndexName,
   streamPartsToIndexPattern,
   indexNameToDataStreamParts,
+  extractIndexNameFromBackingIndex,
 } from './dataset_name';
 
 describe('dataset_name', () => {
@@ -52,4 +53,30 @@ describe('dataset_name', () => {
       });
     });
   });
+
+  describe('extractIndexNameFromBackingIndex', () => {
+    it('returns the correct index name if backing index provieded', () => {
+      expect(
+        extractIndexNameFromBackingIndex(
+          '.ds-logs-apm.app.adservice-default-2024.04.29-000001',
+          'logs'
+        )
+      ).toEqual('logs-apm.app.adservice-default');
+    });
+
+    it('returns the correct index name if index name is passed', () => {
+      expect(extractIndexNameFromBackingIndex('logs-nginx.access-default', 'logs')).toEqual(
+        'logs-nginx.access-default'
+      );
+    });
+
+    it('handles different types', () => {
+      expect(
+        extractIndexNameFromBackingIndex(
+          '.ds-metrics-apm.app.adservice-default-2024.04.29-000001',
+          'metrics'
+        )
+      ).toEqual('metrics-apm.app.adservice-default');
+    });
+  });
 });

x-pack/plugins/observability_solution/dataset_quality/common/utils/dataset_name.ts

@@ -38,3 +38,16 @@ export const indexNameToDataStreamParts = (dataStreamName: string) => {
     namespace,
   };
 };
+
+export const extractIndexNameFromBackingIndex = (
+  indexString: string,
+  type: DataStreamType
+): string => {
+  const pattern: RegExp = new RegExp(
+    `(?:\\.ds-)?(${type}-(?:[^-.]+(?:\\.[^.]+)+)-[^-]+)-\\d{4}\\.\\d{2}\\.\\d{2}-\\d{6}`
+  );
+
+  const match = indexString.match(pattern);
+
+  return match ? match[1] : indexString;
+};