ML: changing JobResultsProvider.getForecastRequestStats to support > 1 index (#37157)

* ML: changing JobResultsProvider.getForecastRequestStats to support more than one index

* moving to use idsQuery()

x-pack/plugin/ml/qa/native-multi-node-tests/src/test/java/org/elasticsearch/xpack/ml/integration/MlNativeAutodetectIntegTestCase.java

@@ -6,7 +6,6 @@
 package org.elasticsearch.xpack.ml.integration;
 
 import org.elasticsearch.action.admin.cluster.node.tasks.list.ListTasksRequest;
-import org.elasticsearch.action.get.GetResponse;
 import org.elasticsearch.action.search.SearchResponse;
 import org.elasticsearch.action.support.master.AcknowledgedResponse;
 import org.elasticsearch.client.Client;
@@ -348,17 +347,19 @@ abstract class MlNativeAutodetectIntegTestCase extends ESIntegTestCase {
     }
 
     protected ForecastRequestStats getForecastStats(String jobId, String forecastId) {
-        GetResponse getResponse = client().prepareGet()
-                .setIndex(AnomalyDetectorsIndex.jobResultsAliasedName(jobId))
-                .setId(ForecastRequestStats.documentId(jobId, forecastId))
-                .execute().actionGet();
+        SearchResponse searchResponse = client().prepareSearch(AnomalyDetectorsIndex.jobResultsAliasedName(jobId))
+            .setQuery(QueryBuilders.idsQuery().addIds(ForecastRequestStats.documentId(jobId, forecastId)))
+            .get();
 
-        if (getResponse.isExists() == false) {
+        if (searchResponse.getHits().getHits().length == 0) {
             return null;
         }
+
+        assertThat(searchResponse.getHits().getHits().length, equalTo(1));
+
         try (XContentParser parser = XContentFactory.xContent(XContentType.JSON).createParser(
                     NamedXContentRegistry.EMPTY, DeprecationHandler.THROW_UNSUPPORTED_OPERATION,
-                    getResponse.getSourceAsBytesRef().streamInput())) {
+                    searchResponse.getHits().getHits()[0].getSourceRef().streamInput())) {
             return ForecastRequestStats.STRICT_PARSER.apply(parser, null);
         } catch (IOException e) {
             throw new IllegalStateException(e);
@@ -398,7 +399,6 @@ abstract class MlNativeAutodetectIntegTestCase extends ESIntegTestCase {
 
     protected List<Forecast> getForecasts(String jobId, ForecastRequestStats forecastRequestStats) {
         List<Forecast> forecasts = new ArrayList<>();
-
         SearchResponse searchResponse = client().prepareSearch(AnomalyDetectorsIndex.jobResultsIndexPrefix() + "*")
                 .setSize((int) forecastRequestStats.getRecordCount())
                 .setQuery(QueryBuilders.boolQuery()

x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/job/persistence/JobResultsProvider.java

@@ -490,20 +490,6 @@ public class JobResultsProvider {
         }
     }
 
-    private <T, U> T parseGetHit(GetResponse getResponse, BiFunction<XContentParser, U, T> objectParser,
-                                 Consumer<Exception> errorHandler) {
-        BytesReference source = getResponse.getSourceAsBytesRef();
-
-        try (InputStream stream = source.streamInput();
-             XContentParser parser = XContentFactory.xContent(XContentType.JSON)
-                     .createParser(NamedXContentRegistry.EMPTY, LoggingDeprecationHandler.INSTANCE, stream)) {
-            return objectParser.apply(parser, null);
-        } catch (IOException e) {
-            errorHandler.accept(new ElasticsearchParseException("failed to parse " + getResponse.getType(), e));
-            return null;
-        }
-    }
-
     /**
      * Search for buckets with the parameters in the {@link BucketsQueryBuilder}
      * Uses the internal client, so runs as the _xpack user
@@ -957,19 +943,6 @@ public class JobResultsProvider {
                 ), client::search);
     }
 
-    private <U, T> void getResult(String jobId, String resultDescription, GetRequest get, BiFunction<XContentParser, U, T> objectParser,
-            Consumer<Result<T>> handler, Consumer<Exception> errorHandler, Supplier<T> notFoundSupplier) {
-
-        executeAsyncWithOrigin(client.threadPool().getThreadContext(), ML_ORIGIN, get, ActionListener.<GetResponse>wrap(getDocResponse -> {
-            if (getDocResponse.isExists()) {
-                handler.accept(new Result<>(getDocResponse.getIndex(), parseGetHit(getDocResponse, objectParser, errorHandler)));
-            } else {
-                LOGGER.trace("No {} for job with id {}", resultDescription, jobId);
-                handler.accept(new Result<>(null, notFoundSupplier.get()));
-            }
-        }, errorHandler), client::get);
-    }
-
     private SearchRequestBuilder createLatestModelSizeStatsSearch(String indexName) {
         return client.prepareSearch(indexName)
                 .setSize(1)
@@ -1115,11 +1088,14 @@ public class JobResultsProvider {
     public void getForecastRequestStats(String jobId, String forecastId, Consumer<ForecastRequestStats> handler,
             Consumer<Exception> errorHandler) {
         String indexName = AnomalyDetectorsIndex.jobResultsAliasedName(jobId);
-        GetRequest getRequest = new GetRequest(indexName, ElasticsearchMappings.DOC_TYPE,
-                ForecastRequestStats.documentId(jobId, forecastId));
-
-        getResult(jobId, ForecastRequestStats.RESULTS_FIELD.getPreferredName(), getRequest, ForecastRequestStats.LENIENT_PARSER,
-                result -> handler.accept(result.result), errorHandler, () -> null);
+        SearchRequestBuilder forecastSearch = client.prepareSearch(indexName)
+            .setQuery(QueryBuilders.idsQuery().addIds(ForecastRequestStats.documentId(jobId, forecastId)));
+
+        searchSingleResult(jobId,
+            ForecastRequestStats.RESULTS_FIELD.getPreferredName(),
+            forecastSearch,
+            ForecastRequestStats.LENIENT_PARSER,result -> handler.accept(result.result),
+            errorHandler, () -> null);
     }
 
     public void getForecastStats(String jobId, Consumer<ForecastStats> handler, Consumer<Exception> errorHandler) {

x-pack/plugin/ml/src/test/java/org/elasticsearch/xpack/ml/job/persistence/JobResultsProviderTests.java

@@ -11,7 +11,6 @@ import org.elasticsearch.Version;
 import org.elasticsearch.action.ActionListener;
 import org.elasticsearch.action.admin.indices.create.CreateIndexRequest;
 import org.elasticsearch.action.admin.indices.mapping.get.GetMappingsResponse;
-import org.elasticsearch.action.get.GetResponse;
 import org.elasticsearch.action.search.MultiSearchRequest;
 import org.elasticsearch.action.search.MultiSearchResponse;
 import org.elasticsearch.action.search.SearchRequest;
@@ -834,13 +833,6 @@ public class JobResultsProviderTests extends ESTestCase {
         return new JobResultsProvider(client, Settings.EMPTY);
     }
 
-    private static GetResponse createGetResponse(boolean exists, Map<String, Object> source) throws IOException {
-        GetResponse getResponse = mock(GetResponse.class);
-        when(getResponse.isExists()).thenReturn(exists);
-        when(getResponse.getSourceAsBytesRef()).thenReturn(BytesReference.bytes(XContentFactory.jsonBuilder().map(source)));
-        return getResponse;
-    }
-
     private static SearchResponse createSearchResponse(List<Map<String, Object>> source) throws IOException {
         SearchResponse response = mock(SearchResponse.class);
         List<SearchHit> list = new ArrayList<>();