Add age_in_millis to ILM Explain Response

Author: gmjehovich

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/ilm/IndexLifecycleExplainResponse.java

@@ -51,6 +51,7 @@ public class IndexLifecycleExplainResponse implements ToXContentObject, Writeabl
     private static final ParseField PREVIOUS_STEP_INFO_FIELD = new ParseField("previous_step_info");
     private static final ParseField PHASE_EXECUTION_INFO = new ParseField("phase_execution");
     private static final ParseField AGE_FIELD = new ParseField("age");
+    private static final ParseField AGE_IN_MILLIS_FIELD = new ParseField("age_in_millis");
     private static final ParseField TIME_SINCE_INDEX_CREATION_FIELD = new ParseField("time_since_index_creation");
     private static final ParseField REPOSITORY_NAME = new ParseField("repository_name");
     private static final ParseField SHRINK_INDEX_NAME = new ParseField("shrink_index_name");
@@ -528,6 +529,7 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
                     lifecycleDate
                 );
                 builder.field(AGE_FIELD.getPreferredName(), getAge(nowSupplier).toHumanReadableString(2));
+                builder.field(AGE_IN_MILLIS_FIELD.getPreferredName(), getAge(nowSupplier).getMillis());
             }
             if (phase != null) {
                 builder.field(PHASE_FIELD.getPreferredName(), phase);

x-pack/plugin/ilm/qa/multi-node/src/javaRestTest/java/org/elasticsearch/xpack/ilm/ExplainLifecycleIT.java

@@ -207,6 +207,7 @@ public void testExplainIndicesWildcard() throws Exception {
             assertThat(explainIndexWithMissingPolicy.get("action"), is(nullValue()));
             assertThat(explainIndexWithMissingPolicy.get("step"), is(ErrorStep.NAME));
             assertThat(explainIndexWithMissingPolicy.get("age"), is(nullValue()));
+            assertThat(explainIndexWithMissingPolicy.get("age_in_millis"), is(nullValue()));
             assertThat(explainIndexWithMissingPolicy.get("failed_step"), is(nullValue()));
             Map<String, Object> stepInfo = (Map<String, Object>) explainIndexWithMissingPolicy.get("step_info");
             assertThat(stepInfo, is(notNullValue()));
@@ -343,6 +344,7 @@ private void assertManagedIndex(Map<String, Object> explainIndexMap) {
         assertThat(explainIndexMap.get("step"), is("complete"));
         assertThat(explainIndexMap.get("phase_time_millis"), is(notNullValue()));
         assertThat(explainIndexMap.get("age"), is(notNullValue()));
+        assertThat(explainIndexMap.get("age_in_millis"), is(notNullValue()));
         assertThat(explainIndexMap.get("phase_execution"), is(notNullValue()));
         assertThat(explainIndexMap.get("failed_step"), is(nullValue()));
         assertThat(explainIndexMap.get("step_info"), is(nullValue()));