add sum and count for DistributionDataPoint (#1669)

Fixes #1610

Signed-off-by: Gregor Zeitlinger <[email protected]>

Author: zeitlinger

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/datapoints/DistributionDataPoint.java

@@ -19,6 +19,12 @@
  */
 public interface DistributionDataPoint extends DataPoint, TimerApi {
 
+  /** Get the count of observations. */
+  long getCount();
+
+  /** Get the sum of all observed values. */
+  double getSum();
+
   /** Observe {@code value}. */
   void observe(double value);
 

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/Histogram.java

@@ -170,6 +170,16 @@ private Histogram(Histogram.Builder builder, PrometheusProperties prometheusProp
     }
   }
 
+  @Override
+  public double getSum() {
+    return getNoLabels().getSum();
+  }
+
+  @Override
+  public long getCount() {
+    return getNoLabels().getCount();
+  }
+
   @Override
   public void observe(double amount) {
     getNoLabels().observe(amount);
@@ -210,6 +220,16 @@ private DataPoint() {
       maybeScheduleNextReset();
     }
 
+    @Override
+    public double getSum() {
+      return sum.sum();
+    }
+
+    @Override
+    public long getCount() {
+      return count.sum();
+    }
+
     @Override
     public void observe(double value) {
       if (Double.isNaN(value)) {

prometheus-metrics-core/src/main/java/io/prometheus/metrics/core/metrics/Summary.java

@@ -84,6 +84,16 @@ private List<CKMSQuantiles.Quantile> makeQuantiles(MetricsProperties[] propertie
     return result;
   }
 
+  @Override
+  public double getSum() {
+    return getNoLabels().getSum();
+  }
+
+  @Override
+  public long getCount() {
+    return getNoLabels().getCount();
+  }
+
   @Override
   public void observe(double amount) {
     getNoLabels().observe(amount);
@@ -143,6 +153,16 @@ private DataPoint() {
       }
     }
 
+    @Override
+    public double getSum() {
+      return sum.sum();
+    }
+
+    @Override
+    public long getCount() {
+      return count.sum();
+    }
+
     @Override
     public void observe(double value) {
       if (Double.isNaN(value)) {

prometheus-metrics-core/src/test/java/io/prometheus/metrics/core/metrics/HistogramTest.java

@@ -1366,6 +1366,8 @@ private ClassicHistogramBucket getBucket(Histogram histogram, double le, String.
   public void testObserve() {
     Histogram noLabels = Histogram.builder().name("test").build();
     noLabels.observe(2);
+    assertThat(noLabels.getCount()).isOne();
+    assertThat(noLabels.getSum()).isCloseTo(2.0, offset(.0));
     assertThat(getData(noLabels).getCount()).isOne();
     assertThat(getData(noLabels).getSum()).isCloseTo(2.0, offset(.0));
     assertThat(getBucket(noLabels, 1).getCount()).isZero();
@@ -1450,6 +1452,9 @@ public void testObserveWithLabels() {
             .labelNames("path", "status")
             .build();
     histogram.labelValues("/hello", "200").observe(0.11);
+    DistributionDataPoint distributionDataPoint = histogram.labelValues("/hello", "200");
+    assertThat(distributionDataPoint.getCount()).isOne();
+    assertThat(distributionDataPoint.getSum()).isCloseTo(0.11, offset(.0));
     histogram.labelValues("/hello", "200").observe(0.2);
     histogram.labelValues("/hello", "500").observe(0.19);
     HistogramSnapshot.HistogramDataPointSnapshot data200 =

prometheus-metrics-core/src/test/java/io/prometheus/metrics/core/metrics/SummaryTest.java

@@ -5,6 +5,7 @@
 import static org.assertj.core.api.Assertions.fail;
 import static org.assertj.core.data.Offset.offset;
 
+import io.prometheus.metrics.core.datapoints.DistributionDataPoint;
 import io.prometheus.metrics.core.datapoints.Timer;
 import io.prometheus.metrics.model.registry.PrometheusRegistry;
 import io.prometheus.metrics.model.snapshots.Label;
@@ -64,13 +65,18 @@ public void setUp() {
   @Test
   public void testObserve() {
     noLabels.observe(2);
+    assertThat(noLabels.getCount()).isOne();
+    assertThat(noLabels.getSum()).isCloseTo(2.0, offset(.0));
     assertThat(getCount(noLabels, Labels.EMPTY)).isOne();
     assertThat(getSum(noLabels, Labels.EMPTY)).isCloseTo(2.0, offset(.001));
     noLabels.observe(3);
     assertThat(getCount(noLabels, Labels.EMPTY)).isEqualTo(2);
     assertThat(getSum(noLabels, Labels.EMPTY)).isCloseTo(5.0, offset(.001));
 
     withLabels.labelValues(label.getValue()).observe(4);
+    DistributionDataPoint distributionDataPoint = withLabels.labelValues(label.getValue());
+    assertThat(distributionDataPoint.getCount()).isOne();
+    assertThat(distributionDataPoint.getSum()).isCloseTo(4.0, offset(.0));
     assertThat(getCount(withLabels, labels)).isOne();
     assertThat(getSum(withLabels, labels)).isCloseTo(4.0, offset(.001));