Add an APM metric to aggregations usage (#108110)

This wires up the "new" APM metrics integration to the existing Aggregations usage tracking system. It introduces one new metric, a LongCounter named es.search.query.aggregations.total, which has dimensions for the specific aggregation being run, and the values source type we resolved it to.

---------

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>

server/src/main/java/org/elasticsearch/node/NodeConstruction.java

@@ -257,7 +257,7 @@ static NodeConstruction prepareConstruction(
             ThreadPool threadPool = constructor.createThreadPool(settings, telemetryProvider.getMeterRegistry());
             SettingsModule settingsModule = constructor.validateSettings(initialEnvironment.settings(), settings, threadPool);
 
-            SearchModule searchModule = constructor.createSearchModule(settingsModule.getSettings(), threadPool);
+            SearchModule searchModule = constructor.createSearchModule(settingsModule.getSettings(), threadPool, telemetryProvider);
             constructor.createClientAndRegistries(settingsModule.getSettings(), threadPool, searchModule);
             DocumentParsingProvider documentParsingProvider = constructor.getDocumentParsingProvider();
 
@@ -525,9 +525,9 @@ private SettingsModule validateSettings(Settings envSettings, Settings settings,
         return settingsModule;
     }
 
-    private SearchModule createSearchModule(Settings settings, ThreadPool threadPool) {
+    private SearchModule createSearchModule(Settings settings, ThreadPool threadPool, TelemetryProvider telemetryProvider) {
         IndexSearcher.setMaxClauseCount(SearchUtils.calculateMaxClauseValue(threadPool));
-        return new SearchModule(settings, pluginsService.filterPlugins(SearchPlugin.class).toList());
+        return new SearchModule(settings, pluginsService.filterPlugins(SearchPlugin.class).toList(), telemetryProvider);
     }
 
     /**

server/src/main/java/org/elasticsearch/search/SearchModule.java

@@ -254,6 +254,7 @@
 import org.elasticsearch.search.vectors.KnnScoreDocQueryBuilder;
 import org.elasticsearch.search.vectors.KnnVectorQueryBuilder;
 import org.elasticsearch.search.vectors.QueryVectorBuilder;
+import org.elasticsearch.telemetry.TelemetryProvider;
 import org.elasticsearch.xcontent.NamedXContentRegistry;
 import org.elasticsearch.xcontent.ParseField;
 import org.elasticsearch.xcontent.XContentParser;
@@ -289,6 +290,11 @@ public class SearchModule {
         Setting.Property.NodeScope
     );
 
+    /**
+     * Metric name for aggregation usage statistics
+     */
+    private final TelemetryProvider telemetryProvider;
+
     private final Map<String, Highlighter> highlighters;
 
     private final List<FetchSubPhase> fetchSubPhases = new ArrayList<>();
@@ -306,7 +312,19 @@ public class SearchModule {
      * @param plugins List of included {@link SearchPlugin} objects.
      */
     public SearchModule(Settings settings, List<SearchPlugin> plugins) {
+        this(settings, plugins, TelemetryProvider.NOOP);
+    }
+
+    /**
+     * Constructs a new SearchModule object
+     *
+     * @param settings          Current settings
+     * @param plugins           List of included {@link SearchPlugin} objects.
+     * @param telemetryProvider
+     */
+    public SearchModule(Settings settings, List<SearchPlugin> plugins, TelemetryProvider telemetryProvider) {
         this.settings = settings;
+        this.telemetryProvider = telemetryProvider;
         registerSuggesters(plugins);
         highlighters = setupHighlighters(settings, plugins);
         registerScoreFunctions(plugins);
@@ -352,7 +370,7 @@ public Map<String, Highlighter> getHighlighters() {
     }
 
     private ValuesSourceRegistry registerAggregations(List<SearchPlugin> plugins) {
-        ValuesSourceRegistry.Builder builder = new ValuesSourceRegistry.Builder();
+        ValuesSourceRegistry.Builder builder = new ValuesSourceRegistry.Builder(telemetryProvider.getMeterRegistry());
 
         registerAggregation(
             new AggregationSpec(AvgAggregationBuilder.NAME, AvgAggregationBuilder::new, AvgAggregationBuilder.PARSER).addResultReader(

server/src/main/java/org/elasticsearch/search/aggregations/support/AggregationUsageService.java

@@ -9,22 +9,35 @@
 package org.elasticsearch.search.aggregations.support;
 
 import org.elasticsearch.node.ReportingService;
+import org.elasticsearch.telemetry.metric.LongCounter;
+import org.elasticsearch.telemetry.metric.MeterRegistry;
 
 import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.atomic.LongAdder;
 
 public class AggregationUsageService implements ReportingService<AggregationInfo> {
+    private static final String ES_SEARCH_QUERY_AGGREGATIONS_TOTAL_COUNT = "es.search.query.aggregations.total";
+    private final String AGGREGATION_NAME_KEY = "aggregation_name";
+    private final String VALUES_SOURCE_KEY = "values_source";
+    private final LongCounter aggregationsUsageCounter;
     private final Map<String, Map<String, LongAdder>> aggs;
     private final AggregationInfo info;
 
     public static final String OTHER_SUBTYPE = "other";
 
     public static class Builder {
         private final Map<String, Map<String, LongAdder>> aggs;
+        private final MeterRegistry meterRegistry;
 
         public Builder() {
+            this(MeterRegistry.NOOP);
+        }
+
+        public Builder(MeterRegistry meterRegistry) {
             aggs = new HashMap<>();
+            assert meterRegistry != null;
+            this.meterRegistry = meterRegistry;
         }
 
         public void registerAggregationUsage(String aggregationName) {
@@ -45,9 +58,16 @@ public AggregationUsageService build() {
         }
     }
 
+    // Attribute names for the metric
+
     private AggregationUsageService(Builder builder) {
         this.aggs = builder.aggs;
         info = new AggregationInfo(aggs);
+        this.aggregationsUsageCounter = builder.meterRegistry.registerLongCounter(
+            ES_SEARCH_QUERY_AGGREGATIONS_TOTAL_COUNT,
+            "Aggregations usage",
+            "count"
+        );
     }
 
     public void incAggregationUsage(String aggregationName, String valuesSourceType) {
@@ -61,6 +81,8 @@ public void incAggregationUsage(String aggregationName, String valuesSourceType)
             assert adder != null : "Unknown subtype [" + aggregationName + "][" + valuesSourceType + "]";
         }
         assert valuesSourceMap != null : "Unknown aggregation [" + aggregationName + "][" + valuesSourceType + "]";
+        // tests will have a no-op implementation here
+        aggregationsUsageCounter.incrementBy(1, Map.of(AGGREGATION_NAME_KEY, aggregationName, VALUES_SOURCE_KEY, valuesSourceType));
     }
 
     public Map<String, Object> getUsageStats() {

server/src/main/java/org/elasticsearch/search/aggregations/support/ValuesSourceRegistry.java

@@ -10,6 +10,7 @@
 import org.elasticsearch.index.query.SearchExecutionContext;
 import org.elasticsearch.search.SearchModule;
 import org.elasticsearch.search.aggregations.AggregationExecutionException;
+import org.elasticsearch.telemetry.metric.MeterRegistry;
 
 import java.util.AbstractMap;
 import java.util.ArrayList;
@@ -58,7 +59,11 @@ public static class Builder {
         private final Map<RegistryKey<?>, List<Map.Entry<ValuesSourceType, ?>>> aggregatorRegistry = new HashMap<>();
 
         public Builder() {
-            this.usageServiceBuilder = new AggregationUsageService.Builder();
+            this(MeterRegistry.NOOP);
+        }
+
+        public Builder(MeterRegistry meterRegistry) {
+            this.usageServiceBuilder = new AggregationUsageService.Builder(meterRegistry);
         }
 
         /**