Add buildMetricValue method to histogram data points

Author: felixbarny

x-pack/plugin/otel-data/src/main/java/org/elasticsearch/xpack/oteldata/otlp/datapoint/DataPoint.java

@@ -184,6 +184,18 @@ public String getMetricName() {
             return metric.getName();
         }
 
+        @Override
+        public void buildMetricValue(XContentBuilder builder) throws IOException {
+            builder.startObject();
+            builder.startArray("counts");
+            HistogramConverter.counts(dataPoint, builder::value);
+            builder.endArray();
+            builder.startArray("values");
+            HistogramConverter.centroidValues(dataPoint, builder::value);
+            builder.endArray();
+            builder.endObject();
+        }
+
         @Override
         public String getDynamicTemplate() {
             return "histogram";
@@ -225,6 +237,18 @@ public String getMetricName() {
             return metric.getName();
         }
 
+        @Override
+        public void buildMetricValue(XContentBuilder builder) throws IOException {
+            builder.startObject();
+            builder.startArray("counts");
+            HistogramConverter.counts(dataPoint, builder::value);
+            builder.endArray();
+            builder.startArray("values");
+            HistogramConverter.centroidValues(dataPoint, builder::value);
+            builder.endArray();
+            builder.endObject();
+        }
+
         @Override
         public String getDynamicTemplate() {
             return "histogram";

x-pack/plugin/otel-data/src/test/java/org/elasticsearch/xpack/oteldata/otlp/docbuilder/MetricDocumentBuilderTests.java

@@ -10,6 +10,9 @@
 import io.opentelemetry.proto.common.v1.InstrumentationScope;
 import io.opentelemetry.proto.common.v1.KeyValue;
 import io.opentelemetry.proto.metrics.v1.AggregationTemporality;
+import io.opentelemetry.proto.metrics.v1.ExponentialHistogramDataPoint;
+import io.opentelemetry.proto.metrics.v1.HistogramDataPoint;
+import io.opentelemetry.proto.metrics.v1.Metric;
 import io.opentelemetry.proto.metrics.v1.NumberDataPoint;
 import io.opentelemetry.proto.resource.v1.Resource;
 
@@ -32,8 +35,11 @@
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 
+import static io.opentelemetry.proto.metrics.v1.AggregationTemporality.AGGREGATION_TEMPORALITY_DELTA;
 import static org.elasticsearch.xpack.oteldata.otlp.OtlpUtils.createDoubleDataPoint;
+import static org.elasticsearch.xpack.oteldata.otlp.OtlpUtils.createExponentialHistogramMetric;
 import static org.elasticsearch.xpack.oteldata.otlp.OtlpUtils.createGaugeMetric;
+import static org.elasticsearch.xpack.oteldata.otlp.OtlpUtils.createHistogramMetric;
 import static org.elasticsearch.xpack.oteldata.otlp.OtlpUtils.createLongDataPoint;
 import static org.elasticsearch.xpack.oteldata.otlp.OtlpUtils.createSumMetric;
 import static org.elasticsearch.xpack.oteldata.otlp.OtlpUtils.keyValue;
@@ -191,4 +197,71 @@ public void testEmptyFields() throws IOException {
         assertThat(doc.evaluate("unit"), is(nullValue()));
     }
 
+    public void testExponentialHistogram() throws Exception{
+        Resource resource = Resource.newBuilder().build();
+        InstrumentationScope scope = InstrumentationScope.newBuilder().build();
+
+        ExponentialHistogramDataPoint dataPoint = ExponentialHistogramDataPoint.newBuilder()
+            .setTimeUnixNano(timestamp)
+            .setStartTimeUnixNano(startTimestamp)
+            .setZeroCount(1)
+            .setPositive(ExponentialHistogramDataPoint.Buckets.newBuilder().setOffset(0).addAllBucketCounts(List.of(1L, 1L)))
+            .setNegative(ExponentialHistogramDataPoint.Buckets.newBuilder().setOffset(0).addAllBucketCounts(List.of(1L, 1L)))
+            .build();
+        Metric metric = createExponentialHistogramMetric("exponential_histogram", "", List.of(), AGGREGATION_TEMPORALITY_DELTA);
+        List<DataPoint> dataPoints = List.of(new DataPoint.ExponentialHistogram(dataPoint, metric));
+
+        DataPointGroupingContext.DataPointGroup dataPointGroup = new DataPointGroupingContext.DataPointGroup(
+            resource,
+            null,
+            scope,
+            null,
+            List.of(),
+            "",
+            dataPoints,
+            "metrics-generic.otel-default"
+        );
+
+        XContentBuilder builder = XContentFactory.contentBuilder(XContentType.JSON);
+        HashMap<String, String> dynamicTemplates = documentBuilder.buildMetricDocument(builder, dataPointGroup);
+
+        ObjectPath doc = ObjectPath.createFromXContent(JsonXContent.jsonXContent, BytesReference.bytes(builder));
+        assertThat(doc.evaluate("metrics.exponential_histogram.values"), equalTo(List.of(-3.0, -1.5, 0.0, 1.5, 3.0)));
+        assertThat(doc.evaluate("metrics.exponential_histogram.counts"), equalTo(List.of(1, 1, 1, 1, 1)));
+        assertThat(dynamicTemplates, hasEntry("metrics.exponential_histogram", "histogram"));
+    }
+
+    public void testHistogram() throws Exception{
+        Resource resource = Resource.newBuilder().build();
+        InstrumentationScope scope = InstrumentationScope.newBuilder().build();
+
+        HistogramDataPoint dataPoint = HistogramDataPoint.newBuilder()
+            .setTimeUnixNano(timestamp)
+            .setStartTimeUnixNano(startTimestamp)
+            .addBucketCounts(10L)
+            .addExplicitBounds(5.0)
+            .build();
+        Metric metric = createHistogramMetric("histogram", "", List.of(), AGGREGATION_TEMPORALITY_DELTA);
+        List<DataPoint> dataPoints = List.of(new DataPoint.Histogram(dataPoint, metric));
+
+        DataPointGroupingContext.DataPointGroup dataPointGroup = new DataPointGroupingContext.DataPointGroup(
+            resource,
+            null,
+            scope,
+            null,
+            List.of(),
+            "",
+            dataPoints,
+            "metrics-generic.otel-default"
+        );
+
+        XContentBuilder builder = XContentFactory.contentBuilder(XContentType.JSON);
+        HashMap<String, String> dynamicTemplates = documentBuilder.buildMetricDocument(builder, dataPointGroup);
+
+        ObjectPath doc = ObjectPath.createFromXContent(JsonXContent.jsonXContent, BytesReference.bytes(builder));
+        assertThat(doc.evaluate("metrics.histogram.values"), equalTo(List.of(2.5)));
+        assertThat(doc.evaluate("metrics.histogram.counts"), equalTo(List.of(10)));
+        assertThat(dynamicTemplates, hasEntry("metrics.histogram", "histogram"));
+    }
+
 }