[connector/elasticapm]Use exponential histogram from txn metrics (#630)

Author: lahsivjar

connector/elasticapmconnector/config.go

@@ -166,13 +166,7 @@ func (cfg Config) signaltometricsConfig() *signaltometricsconfig.Config {
 		{Key: "metricset.name", DefaultValue: "service_destination"},
 	}
 
-	// TODO switch to exponential histogram once we have optimised
-	// exponential histogram merging.
-	transactionDurationHistogram := &signaltometricsconfig.Histogram{
-		Buckets: []float64{
-			5000, 10000, 25000, 50000, 75000, 100000, 250000, 500000,
-			750000, 1000000, 2500000, 5000000, 7500000, 10000000,
-		},
+	transactionDurationHistogram := &signaltometricsconfig.ExponentialHistogram{
 		Count: "Int(AdjustedCount())",
 		Value: "Microseconds(end_time - start_time)",
 	}
@@ -213,8 +207,8 @@ func (cfg Config) signaltometricsConfig() *signaltometricsconfig.Config {
 				Key:          "elasticsearch.mapping.hints",
 				DefaultValue: []any{"_doc_count"},
 			}),
-			Unit:      "us",
-			Histogram: transactionDurationHistogram,
+			Unit:                 "us",
+			ExponentialHistogram: transactionDurationHistogram,
 		}, {
 			Name:                      "transaction.duration.summary",
 			Description:               "APM service transaction aggregated metrics as summary",
@@ -233,8 +227,8 @@ func (cfg Config) signaltometricsConfig() *signaltometricsconfig.Config {
 				Key:          "elasticsearch.mapping.hints",
 				DefaultValue: []any{"_doc_count"},
 			}),
-			Unit:      "us",
-			Histogram: transactionDurationHistogram,
+			Unit:                 "us",
+			ExponentialHistogram: transactionDurationHistogram,
 		}, {
 			Name:                      "transaction.duration.summary",
 			Description:               "APM transaction aggregated metrics as summary",

connector/elasticapmconnector/testdata/logs/service_summary/aggregated_metrics.yaml

@@ -1,73 +1,73 @@
 resourceMetrics:
   - resource:
       attributes:
-        - key: service.name
+        - key: agent.name
           value:
-            stringValue: foo
+            stringValue: unknown
         - key: deployment.environment
           value:
             stringValue: qa
+        - key: service.name
+          value:
+            stringValue: foo
         - key: telemetry.sdk.language
           value:
             stringValue: go
-        - key: agent.name
-          value:
-            stringValue: unknown
     scopeMetrics:
-      - scope:
-          name: github.com/open-telemetry/opentelemetry-collector-contrib/connector/signaltometricsconnector
-        metrics:
+      - metrics:
           - name: service_summary
             sum:
               aggregationTemporality: 1
               dataPoints:
-                - asInt: 1
+                - asInt: "1"
                   attributes:
                     - key: data_stream.dataset
                       value:
                         stringValue: service_summary.1m
+                    - key: metricset.interval
+                      value:
+                        stringValue: 1m
                     - key: metricset.name
                       value:
                         stringValue: service_summary
-                    - key: metricset.interval
-                      value:
-                        stringValue: "1m"
                     - key: processor.event
                       value:
                         stringValue: metric
           - name: service_summary
             sum:
               aggregationTemporality: 1
               dataPoints:
-                - asInt: 1
+                - asInt: "1"
                   attributes:
                     - key: data_stream.dataset
                       value:
                         stringValue: service_summary.10m
+                    - key: metricset.interval
+                      value:
+                        stringValue: 10m
                     - key: metricset.name
                       value:
                         stringValue: service_summary
-                    - key: metricset.interval
-                      value:
-                        stringValue: "10m"
                     - key: processor.event
                       value:
                         stringValue: metric
           - name: service_summary
             sum:
               aggregationTemporality: 1
               dataPoints:
-                - asInt: 1
+                - asInt: "1"
                   attributes:
                     - key: data_stream.dataset
                       value:
                         stringValue: service_summary.60m
+                    - key: metricset.interval
+                      value:
+                        stringValue: 60m
                     - key: metricset.name
                       value:
                         stringValue: service_summary
-                    - key: metricset.interval
-                      value:
-                        stringValue: "60m"
                     - key: processor.event
                       value:
                         stringValue: metric
+        scope:
+          name: github.com/open-telemetry/opentelemetry-collector-contrib/connector/signaltometricsconnector

connector/elasticapmconnector/testdata/metrics/service_summary/aggregated_metrics.yaml

@@ -1,6 +1,9 @@
 resourceMetrics:
   - resource:
       attributes:
+        - key: agent.name
+          value:
+            stringValue: unknown
         - key: deployment.environment
           value:
             stringValue: qa
@@ -10,9 +13,6 @@ resourceMetrics:
         - key: telemetry.sdk.language
           value:
             stringValue: go
-        - key: agent.name
-          value:
-            stringValue: unknown
     scopeMetrics:
       - metrics:
           - name: service_summary