Use snapshot's latest result time rather than snapshot's creation time when creating an annotation (elastic#56093) (elastic#56103)

Author: przemekwitek

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ml/job/process/autodetect/state/ModelSnapshot.java

@@ -89,6 +89,10 @@ private static ObjectParser<Builder, Void> createParser(boolean ignoreUnknownFie
      */
     private final Version minVersion;
 
+    /**
+     * This is model snapshot's creation wall clock time.
+     * Use {@code latestResultTimeStamp} if you need model time instead.
+     */
     private final Date timestamp;
     private final String description;
     private final String snapshotId;

x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/job/process/autodetect/output/AutodetectResultProcessor.java

@@ -332,8 +332,8 @@ private Annotation createModelSnapshotAnnotation(ModelSnapshot modelSnapshot) {
             Messages.getMessage(Messages.JOB_AUDIT_SNAPSHOT_STORED, modelSnapshot.getSnapshotId()),
             currentTime,
             XPackUser.NAME,
-            modelSnapshot.getTimestamp(),
-            modelSnapshot.getTimestamp(),
+            modelSnapshot.getLatestResultTimeStamp(),
+            modelSnapshot.getLatestResultTimeStamp(),
             jobId,
             currentTime,
             XPackUser.NAME,

x-pack/plugin/ml/src/test/java/org/elasticsearch/xpack/ml/integration/AutodetectResultProcessorIT.java

@@ -482,7 +482,8 @@ private static ModelSizeStats createModelSizeStats() {
     private static ModelSnapshot createModelSnapshot() {
         return new ModelSnapshot.Builder(JOB_ID)
             .setSnapshotId(randomAlphaOfLength(12))
-            .setTimestamp(Date.from(Instant.ofEpochMilli(1000000000)))
+            .setLatestResultTimeStamp(Date.from(Instant.ofEpochMilli(1000_000_000)))
+            .setTimestamp(Date.from(Instant.ofEpochMilli(2000_000_000)))
             .build();
     }
 

x-pack/plugin/ml/src/test/java/org/elasticsearch/xpack/ml/job/process/autodetect/output/AutodetectResultProcessorTests.java

@@ -365,7 +365,8 @@ public void testProcessResult_modelSnapshot() {
         AutodetectResult result = mock(AutodetectResult.class);
         ModelSnapshot modelSnapshot = new ModelSnapshot.Builder(JOB_ID)
             .setSnapshotId("a_snapshot_id")
-            .setTimestamp(Date.from(Instant.ofEpochMilli(1000000000)))
+            .setLatestResultTimeStamp(Date.from(Instant.ofEpochMilli(1000_000_000)))
+            .setTimestamp(Date.from(Instant.ofEpochMilli(2000_000_000)))
             .setMinVersion(Version.CURRENT)
             .build();
         when(result.getModelSnapshot()).thenReturn(modelSnapshot);
@@ -389,8 +390,8 @@ public void testProcessResult_modelSnapshot() {
                 "Job model snapshot with id [a_snapshot_id] stored",
                 Date.from(CURRENT_TIME),
                 XPackUser.NAME,
-                modelSnapshot.getTimestamp(),
-                modelSnapshot.getTimestamp(),
+                Date.from(Instant.ofEpochMilli(1000_000_000)),
+                Date.from(Instant.ofEpochMilli(1000_000_000)),
                 JOB_ID,
                 Date.from(CURRENT_TIME),
                 XPackUser.NAME,