[Profiling] Tighten index name check (#97710)

All profiling-related indices contain a version identifier in their
name. In some places we need to check whether an index exists regardless
of its version. Previously this check was too lenient because it also
considered indices with the same prefix (e.g. a check for
`profiling-stackframes` would also match `profiling-stackframes-all`).
With this commit we tighten the check to match the full name until the
version identifier.

x-pack/plugin/profiler/src/main/java/org/elasticsearch/xpack/profiler/ProfilingIndexManager.java

@@ -354,7 +354,17 @@ public class ProfilingIndexManager extends AbstractProfilingPersistenceManager<P
         }
 
         public boolean isMatchWithoutVersion(String indexName) {
-            return indexName.startsWith("." + namePrefix);
+            String expectedPrefix = "." + namePrefix + "-v";
+            return indexName.startsWith(expectedPrefix) && isVersionNumber(indexName, expectedPrefix.length());
+        }
+
+        private boolean isVersionNumber(String name, int startIndex) {
+            final int versionNumberLength = 3;
+            String versionNumberCandidate = name.substring(startIndex, Math.min(startIndex + versionNumberLength, name.length()));
+            return versionNumberCandidate.length() == versionNumberLength
+                // do an explicit range check here for latin digits as Character#isDigit() also considers other
+                // Unicode digit characters that we don't want to recognize here.
+                && versionNumberCandidate.chars().allMatch((c) -> '0' <= c && c <= '9');
         }
 
         public boolean isMatchWithoutGeneration(String indexName) {

x-pack/plugin/profiler/src/test/java/org/elasticsearch/xpack/profiler/ProfilingIndexManagerTests.java

@@ -227,6 +227,14 @@ public class ProfilingIndexManagerTests extends ESTestCase {
         indicesDeleted.set(0);
     }
 
+    public void testIndexMatchWithoutVersion() {
+        ProfilingIndexManager.ProfilingIndex idx = ProfilingIndexManager.ProfilingIndex.kv("profiling-test", 1);
+        assertTrue(idx.isMatchWithoutVersion(".profiling-test-v002"));
+        assertFalse(idx.isMatchWithoutVersion(".profiling-testing-v001"));
+        assertFalse(idx.isMatchWithoutVersion(".profiling-test-verbose"));
+        assertFalse(idx.isMatchWithoutVersion(".profiling-test-v"));
+    }
+
     private ActionResponse verifyIndexInstalled(
         AtomicInteger calledTimes,
         ActionType<?> action,