fix aggregation metrics config unnecessary force of tags

deployment/helm/ditto/Chart.yaml

@@ -16,7 +16,7 @@ description: |
   A digital twin is a virtual, cloud based, representation of his real world counterpart
   (real world “Things”, e.g. devices like sensors, smart heating, connected cars, smart grids, EV charging stations etc).
 type: application
-version: 3.6.3  # chart version is effectively set by release-job
+version: 3.6.4  # chart version is effectively set by release-job
 appVersion: 3.6.3
 keywords:
   - iot-chart

thingsearch/service/src/main/java/org/eclipse/ditto/thingsearch/service/common/config/DefaultCustomAggregationMetricConfig.java

@@ -161,9 +161,16 @@ private void validateConfig() {
             });
 
             final Set<String> requiredGroupByPlaceholders = getDeclaredGroupByPlaceholdersExpressions(getTags());
-            if (!requiredGroupByPlaceholders.equals(getGroupBy().keySet())) {
-                throw new IllegalArgumentException("Custom search metric Gauge for metric <"
-                + metricName + "> must have the same groupBy fields as the configured placeholder expressions in tags. Required: " + requiredGroupByPlaceholders + " Configured: " + getGroupBy().keySet());
+            List<String> missing = new ArrayList<>();
+            requiredGroupByPlaceholders.forEach(placeholder -> {
+                if (!getGroupBy().containsKey(placeholder)) {
+                    missing.add(placeholder);
+                }
+            });
+            if (!missing.isEmpty()){
+                throw new IllegalArgumentException("Custom search metric Gauge for metric <" + metricName
+                        + "> must contain in the groupBy fields all of the fields used by placeholder expressions in tags. Missing: "
+                        + missing + " Configured: " + getGroupBy().keySet());
             }
     }
 

thingsearch/service/src/main/java/org/eclipse/ditto/thingsearch/service/starter/actors/OperatorAggregateMetricsProviderActor.java

@@ -75,15 +75,15 @@ public final class OperatorAggregateMetricsProviderActor extends AbstractActorWi
     private static final String METRIC_NAME = "metric-name";
 
     private final DittoDiagnosticLoggingAdapter log = DittoLoggerFactory.getDiagnosticLoggingAdapter(this);
-    private final ActorRef thingsAggregatorActorSingletonProxy;
+    private final ActorRef aggregateThingsMetricsActorSingletonProxy;
     private final Map<String, CustomAggregationMetricConfig> customSearchMetricConfigMap;
     private final Map<GageIdentifier, TimestampedGauge> metricsGauges;
     private final Gauge customSearchMetricsGauge;
     private final Map<FilterIdentifier, PlaceholderResolver<Map<String, String>>> inlinePlaceholderResolvers;
 
     @SuppressWarnings("unused")
     private OperatorAggregateMetricsProviderActor(final SearchConfig searchConfig) {
-        this.thingsAggregatorActorSingletonProxy = initializeAggregationThingsMetricsActor(searchConfig);
+        this.aggregateThingsMetricsActorSingletonProxy = initializeAggregationThingsMetricsActor(searchConfig);
         this.customSearchMetricConfigMap = searchConfig.getOperatorMetricsConfig().getCustomAggregationMetricConfigs();
         this.metricsGauges = new HashMap<>();
         this.inlinePlaceholderResolvers = new LinkedHashMap<>();
@@ -150,7 +150,7 @@ private void handleGatheringMetrics(final GatherMetricsCommand gatherMetricsComm
         final AggregateThingsMetrics
                 aggregateThingsMetrics = AggregateThingsMetrics.of(metricName, config.getGroupBy(), namedFilters,
                 Set.of(config.getNamespaces().toArray(new String[0])), dittoHeaders);
-        thingsAggregatorActorSingletonProxy.tell(aggregateThingsMetrics, getSelf());
+        aggregateThingsMetricsActorSingletonProxy.tell(aggregateThingsMetrics, getSelf());
     }