fixing DataStreamLifecycleServiceIT

Author: masseyke

modules/data-streams/src/internalClusterTest/java/org/elasticsearch/datastreams/lifecycle/DataStreamLifecycleServiceIT.java

@@ -104,6 +104,7 @@
 import static org.elasticsearch.index.IndexSettings.LIFECYCLE_ORIGINATION_DATE;
 import static org.elasticsearch.indices.ShardLimitValidator.SETTING_CLUSTER_MAX_SHARDS_PER_NODE;
 import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAcked;
+import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.containsInAnyOrder;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.equalTo;
@@ -785,14 +786,10 @@ public void testErrorRecordingOnRetention() throws Exception {
                 ).get();
                 DataStreamLifecycleHealthInfo dslHealthInfoOnHealthNode = healthNodeResponse.getHealthInfo().dslHealthInfo();
                 assertThat(dslHealthInfoOnHealthNode, is(not(DataStreamLifecycleHealthInfo.NO_DSL_ERRORS)));
-                // perhaps surprisingly rollover and delete are error-ing due to the read_only block on the first generation
-                // index which prevents metadata updates so rolling over the data stream is also blocked (note that both indices error at
-                // the same time so they'll have an equal retry count - the order becomes of the results, usually ordered by retry count,
-                // becomes non deterministic, hence the dynamic matching of index name)
-                assertThat(dslHealthInfoOnHealthNode.dslErrorsInfo().size(), is(2));
+                assertThat(dslHealthInfoOnHealthNode.dslErrorsInfo().size(), is(1));
                 DslErrorInfo errorInfo = dslHealthInfoOnHealthNode.dslErrorsInfo().get(0);
                 assertThat(errorInfo.retryCount(), greaterThanOrEqualTo(3));
-                assertThat(List.of(firstGenerationIndex, secondGenerationIndex).contains(errorInfo.indexName()), is(true));
+                assertThat(errorInfo.indexName(), equalTo(firstGenerationIndex));
             });
 
             GetHealthAction.Response healthResponse = client().execute(GetHealthAction.INSTANCE, new GetHealthAction.Request(true, 1000))
@@ -808,15 +805,12 @@ public void testErrorRecordingOnRetention() throws Exception {
                 assertThat(dslIndicator.impacts(), is(STAGNATING_INDEX_IMPACT));
                 assertThat(
                     dslIndicator.symptom(),
-                    is("2 backing indices have repeatedly encountered errors whilst trying to advance in its lifecycle")
+                    is("A backing index has repeatedly encountered errors whilst trying to advance in its lifecycle")
                 );
 
                 Diagnosis diagnosis = dslIndicator.diagnosisList().get(0);
                 assertThat(diagnosis.definition(), is(STAGNATING_BACKING_INDICES_DIAGNOSIS_DEF));
-                assertThat(
-                    diagnosis.affectedResources().get(0).getValues(),
-                    containsInAnyOrder(firstGenerationIndex, secondGenerationIndex)
-                );
+                assertThat(diagnosis.affectedResources().get(0).getValues(), contains(firstGenerationIndex));
             }
 
             // let's mark the index as writeable and make sure it's deleted and the error store is empty