DATETIME_FORMATTER_CACHING_SETTING experimental feature should not de…

…fault to 'true'

Signed-off-by: Andriy Redko <[email protected]>

CHANGELOG.md

@@ -97,6 +97,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - Improve the error messages for _stats with closed indices ([#13012](https://github.com/opensearch-project/OpenSearch/pull/13012))
 - Ignore BaseRestHandler unconsumed content check as it's always consumed. ([#13290](https://github.com/opensearch-project/OpenSearch/pull/13290))
 - Fix mapper_parsing_exception when using flat_object fields with names longer than 11 characters ([#13259](https://github.com/opensearch-project/OpenSearch/pull/13259))
+- DATETIME_FORMATTER_CACHING_SETTING experimental feature should not default to 'true' ([#13532](https://github.com/opensearch-project/OpenSearch/pull/13532))
 
 ### Security
 

server/src/main/java/org/opensearch/common/util/FeatureFlags.java

@@ -81,7 +81,7 @@ public class FeatureFlags {
 
     public static final Setting<Boolean> DATETIME_FORMATTER_CACHING_SETTING = Setting.boolSetting(
         DATETIME_FORMATTER_CACHING,
-        true,
+        false,
         Property.NodeScope
     );
 

server/src/test/java/org/opensearch/common/util/FeatureFlagTests.java

@@ -39,30 +39,24 @@ public void testNonBooleanFeatureFlag() {
         assertFalse(FeatureFlags.isEnabled(javaVersionProperty));
     }
 
-    public void testBooleanFeatureFlagWithDefaultSetToTrue() {
-        final String testFlag = DATETIME_FORMATTER_CACHING;
-        assertNotNull(testFlag);
-        assertTrue(FeatureFlags.isEnabled(testFlag));
-    }
-
     public void testBooleanFeatureFlagWithDefaultSetToFalse() {
         final String testFlag = IDENTITY;
         FeatureFlags.initializeFeatureFlags(Settings.EMPTY);
         assertNotNull(testFlag);
         assertFalse(FeatureFlags.isEnabled(testFlag));
     }
 
-    public void testBooleanFeatureFlagInitializedWithEmptySettingsAndDefaultSetToTrue() {
+    public void testBooleanFeatureFlagInitializedWithEmptySettingsAndDefaultSetToFalse() {
         final String testFlag = DATETIME_FORMATTER_CACHING;
         FeatureFlags.initializeFeatureFlags(Settings.EMPTY);
         assertNotNull(testFlag);
-        assertTrue(FeatureFlags.isEnabled(testFlag));
+        assertFalse(FeatureFlags.isEnabled(testFlag));
     }
 
     public void testInitializeFeatureFlagsWithExperimentalSettings() {
         FeatureFlags.initializeFeatureFlags(Settings.builder().put(IDENTITY, true).build());
         assertTrue(FeatureFlags.isEnabled(IDENTITY));
-        assertTrue(FeatureFlags.isEnabled(DATETIME_FORMATTER_CACHING));
+        assertFalse(FeatureFlags.isEnabled(DATETIME_FORMATTER_CACHING));
         assertFalse(FeatureFlags.isEnabled(EXTENSIONS));
         // reset FeatureFlags to defaults
         FeatureFlags.initializeFeatureFlags(Settings.EMPTY);