Bugfix: Relax updatedAt validation for WLM workload group creation (opensearch-project#20486)

Signed-off-by: hyanggeun <songsogu@gmail.com>

Author: hyanggeun

CHANGELOG.md

@@ -20,6 +20,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - [segment replication] Fix segment replication infinite retry due to stale metadata checkpoint ([#20551](https://github.com/opensearch-project/OpenSearch/pull/20551))
 - Changing opensearch.cgroups.hierarchy.override causes java.lang.SecurityException exception ([#20565](https://github.com/opensearch-project/OpenSearch/pull/20565))
 - Fix CriteriaBasedCodec to work with delegate codec. ([20442](https://github.com/opensearch-project/OpenSearch/pull/20442))
+- Fix WLM workload group creation failing due to updated_at clock skew ([#20486](https://github.com/opensearch-project/OpenSearch/pull/20486))
 
 ### Dependencies
 - Bump `ch.qos.logback:logback-core` and `ch.qos.logback:logback-classic` from 1.5.24 to 1.5.27 ([#20525](https://github.com/opensearch-project/OpenSearch/pull/20525))

server/src/main/java/org/opensearch/cluster/metadata/WorkloadGroup.java

@@ -69,7 +69,7 @@ public WorkloadGroup(String name, String _id, MutableWorkloadGroupFragment mutab
         if (mutableWorkloadGroupFragment.getResourceLimits().isEmpty()) {
             throw new IllegalArgumentException("WorkloadGroup.resourceLimits should at least have 1 resource limit");
         }
-        if (!isValid(updatedAt)) {
+        if (updatedAt <= 0L) {
             throw new IllegalArgumentException("WorkloadGroup.updatedAtInMillis is not a valid epoch");
         }
 

server/src/test/java/org/opensearch/cluster/metadata/WorkloadGroupTests.java

@@ -179,6 +179,45 @@ public void testValidWorkloadGroup() {
         assertEquals(1717187289, workloadGroup.getUpdatedAtInMillis());
     }
 
+    public void testUpdatedAtAllowsCurrentTimestamp() {
+        long currentTimestamp = Instant.now().getMillis();
+        WorkloadGroup workloadGroup = new WorkloadGroup(
+            "analytics",
+            "_id",
+            new MutableWorkloadGroupFragment(randomMode(), Map.of(ResourceType.MEMORY, randomDoubleBetween(0.01, 0.8, false))),
+            currentTimestamp
+        );
+
+        assertEquals(currentTimestamp, workloadGroup.getUpdatedAtInMillis());
+    }
+
+    public void testUpdatedAtAllowsJitterAroundNow() {
+        long now = Instant.now().getMillis();
+        long[] timestamps = new long[] { Math.max(0L, now - 20L), now + 20L };
+
+        for (long timestamp : timestamps) {
+            WorkloadGroup workloadGroup = new WorkloadGroup(
+                "analytics",
+                "_id",
+                new MutableWorkloadGroupFragment(randomMode(), Map.of(ResourceType.MEMORY, randomDoubleBetween(0.01, 0.8, false))),
+                timestamp
+            );
+            assertEquals(timestamp, workloadGroup.getUpdatedAtInMillis());
+        }
+    }
+
+    public void testUpdatedAtRejectsNegativeTimestamp() {
+        assertThrows(
+            IllegalArgumentException.class,
+            () -> new WorkloadGroup(
+                "analytics",
+                "_id",
+                new MutableWorkloadGroupFragment(randomMode(), Map.of(ResourceType.MEMORY, randomDoubleBetween(0.01, 0.8, false))),
+                -1L
+            )
+        );
+    }
+
     public void testToXContent() throws IOException {
         long currentTimeInMillis = Instant.now().getMillis();
         String workloadGroupId = UUIDs.randomBase64UUID();