Prototype histogram advice API (i.e. Hints)

docs/apidiffs/current_vs_latest/opentelemetry-sdk-testing.txt

@@ -1,2 +1,5 @@
 Comparing source compatibility of  against 
-No changes.
+***  MODIFIED CLASS: PUBLIC io.opentelemetry.sdk.testing.exporter.InMemoryMetricReader  (not serializable)
+	===  CLASS FILE FORMAT VERSION: 52.0 <- 52.0
+	+++  NEW METHOD: PUBLIC(+) STATIC(+) io.opentelemetry.sdk.testing.exporter.InMemoryMetricReader create(io.opentelemetry.sdk.metrics.export.AggregationTemporalitySelector, io.opentelemetry.sdk.metrics.export.DefaultAggregationSelector)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.Aggregation getDefaultAggregation(io.opentelemetry.sdk.metrics.InstrumentType)

extensions/incubator/src/main/java/io/opentelemetry/extension/incubator/metrics/ExtendedDoubleHistogramBuilder.java

@@ -0,0 +1,18 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.extension.incubator.metrics;
+
+import io.opentelemetry.api.metrics.DoubleHistogramBuilder;
+import java.util.function.Consumer;
+
+/** Extended {@link DoubleHistogramBuilder} with experimental APIs. */
+public interface ExtendedDoubleHistogramBuilder extends DoubleHistogramBuilder {
+
+  /** Specify advice for histogram implementations. */
+  default DoubleHistogramBuilder setAdvice(Consumer<HistogramAdviceConfigurer> adviceConsumer) {
+    return this;
+  }
+}

extensions/incubator/src/main/java/io/opentelemetry/extension/incubator/metrics/ExtendedLongHistogramBuilder.java

@@ -0,0 +1,18 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.extension.incubator.metrics;
+
+import io.opentelemetry.api.metrics.LongHistogramBuilder;
+import java.util.function.Consumer;
+
+/** Extended {@link LongHistogramBuilder} with experimental APIs. */
+public interface ExtendedLongHistogramBuilder extends LongHistogramBuilder {
+
+  /** Specify advice for histogram implementations. */
+  default LongHistogramBuilder setAdvice(Consumer<HistogramAdviceConfigurer> adviceConsumer) {
+    return this;
+  }
+}

extensions/incubator/src/main/java/io/opentelemetry/extension/incubator/metrics/HistogramAdviceConfigurer.java

@@ -0,0 +1,17 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.extension.incubator.metrics;
+
+import io.opentelemetry.api.metrics.DoubleHistogram;
+import io.opentelemetry.api.metrics.LongHistogram;
+import java.util.List;
+
+/** Configure advice for implementations of {@link LongHistogram} and {@link DoubleHistogram}. */
+public interface HistogramAdviceConfigurer {
+
+  /** Specify recommended set of explicit bucket boundaries for this histogram. */
+  HistogramAdviceConfigurer setExplicitBucketBoundaries(List<Double> bucketBoundaries);
+}

sdk/all/src/test/java/io/opentelemetry/sdk/OpenTelemetrySdkTest.java

@@ -48,8 +48,11 @@
 import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 
 @ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
 class OpenTelemetrySdkTest {
 
   @RegisterExtension

sdk/metrics/build.gradle.kts

@@ -15,6 +15,7 @@ otelJava.moduleName.set("io.opentelemetry.sdk.metrics")
 dependencies {
   api(project(":api:all"))
   api(project(":sdk:common"))
+  implementation(project(":extensions:incubator"))
 
   compileOnly("org.codehaus.mojo:animal-sniffer-annotations")
 

sdk/metrics/src/debugEnabledTest/java/io/opentelemetry/sdk/metrics/internal/descriptor/InstrumentDescriptorTest.java

@@ -22,44 +22,80 @@ class InstrumentDescriptorTest {
   void equals() {
     InstrumentDescriptor descriptor =
         InstrumentDescriptor.create(
-            "name", "description", "unit", InstrumentType.COUNTER, InstrumentValueType.LONG);
+            "name",
+            "description",
+            "unit",
+            InstrumentType.COUNTER,
+            InstrumentValueType.LONG,
+            Advice.empty());
 
     assertThat(descriptor)
         .isEqualTo(
             InstrumentDescriptor.create(
-                "name", "description", "unit", InstrumentType.COUNTER, InstrumentValueType.LONG));
+                "name",
+                "description",
+                "unit",
+                InstrumentType.COUNTER,
+                InstrumentValueType.LONG,
+                Advice.empty()));
 
     // Validate getSourceInfo() is not equal for otherwise equal descriptors
     assertThat(descriptor.getSourceInfo())
         .isNotEqualTo(
             InstrumentDescriptor.create(
-                    "name", "description", "unit", InstrumentType.COUNTER, InstrumentValueType.LONG)
+                    "name",
+                    "description",
+                    "unit",
+                    InstrumentType.COUNTER,
+                    InstrumentValueType.LONG,
+                    Advice.empty())
                 .getSourceInfo());
 
     // Validate that name, description, unit, type, and value type are considered in equals
     assertThat(descriptor)
         .isNotEqualTo(
             InstrumentDescriptor.create(
-                "foo", "description", "unit", InstrumentType.COUNTER, InstrumentValueType.LONG));
+                "foo",
+                "description",
+                "unit",
+                InstrumentType.COUNTER,
+                InstrumentValueType.LONG,
+                Advice.empty()));
     assertThat(descriptor)
         .isNotEqualTo(
             InstrumentDescriptor.create(
-                "name", "foo", "unit", InstrumentType.COUNTER, InstrumentValueType.LONG));
+                "name",
+                "foo",
+                "unit",
+                InstrumentType.COUNTER,
+                InstrumentValueType.LONG,
+                Advice.empty()));
     assertThat(descriptor)
         .isNotEqualTo(
             InstrumentDescriptor.create(
-                "name", "description", "foo", InstrumentType.COUNTER, InstrumentValueType.LONG));
+                "name",
+                "description",
+                "foo",
+                InstrumentType.COUNTER,
+                InstrumentValueType.LONG,
+                Advice.empty()));
     assertThat(descriptor)
         .isNotEqualTo(
             InstrumentDescriptor.create(
                 "name",
                 "description",
                 "unit",
                 InstrumentType.UP_DOWN_COUNTER,
-                InstrumentValueType.LONG));
+                InstrumentValueType.LONG,
+                Advice.empty()));
     assertThat(descriptor)
         .isNotEqualTo(
             InstrumentDescriptor.create(
-                "name", "description", "unit", InstrumentType.COUNTER, InstrumentValueType.DOUBLE));
+                "name",
+                "description",
+                "unit",
+                InstrumentType.COUNTER,
+                InstrumentValueType.DOUBLE,
+                Advice.empty()));
   }
 }

sdk/metrics/src/debugEnabledTest/java/io/opentelemetry/testing/SourceInfoTest.java

@@ -11,6 +11,7 @@
 import io.opentelemetry.sdk.metrics.InstrumentValueType;
 import io.opentelemetry.sdk.metrics.View;
 import io.opentelemetry.sdk.metrics.internal.debug.SourceInfo;
+import io.opentelemetry.sdk.metrics.internal.descriptor.Advice;
 import io.opentelemetry.sdk.metrics.internal.descriptor.InstrumentDescriptor;
 import io.opentelemetry.sdk.metrics.internal.descriptor.MetricDescriptor;
 import io.opentelemetry.sdk.metrics.internal.state.DebugUtils;
@@ -23,10 +24,10 @@ class SourceInfoTest {
 
   @Test
   void sourceInfoFindsStackTrace() {
-    assertThat(info.shortDebugString()).isEqualTo("SourceInfoTest.java:22");
+    assertThat(info.shortDebugString()).isEqualTo("SourceInfoTest.java:23");
     assertThat(info.multiLineDebugString())
         .startsWith(
-            "\tat io.opentelemetry.testing.SourceInfoTest.<clinit>(SourceInfoTest.java:22)\n");
+            "\tat io.opentelemetry.testing.SourceInfoTest.<clinit>(SourceInfoTest.java:23)\n");
   }
 
   @Test
@@ -40,7 +41,8 @@ void testDuplicateExceptionMessage_pureInstruments() {
                 "description",
                 "unit",
                 InstrumentType.OBSERVABLE_COUNTER,
-                InstrumentValueType.DOUBLE));
+                InstrumentValueType.DOUBLE,
+                Advice.empty()));
     MetricDescriptor simpleWithNewDescription =
         MetricDescriptor.create(
             View.builder().build(),
@@ -50,7 +52,8 @@ void testDuplicateExceptionMessage_pureInstruments() {
                 "description2",
                 "unit2",
                 InstrumentType.COUNTER,
-                InstrumentValueType.LONG));
+                InstrumentValueType.LONG,
+                Advice.empty()));
     assertThat(DebugUtils.duplicateMetricErrorMessage(simple, simpleWithNewDescription))
         .contains("Found duplicate metric definition: name")
         .contains("- InstrumentDescription [description2] does not match [description]")
@@ -76,7 +79,8 @@ void testDuplicateExceptionMessage_viewBasedConflict() {
                 "description",
                 "unit",
                 InstrumentType.HISTOGRAM,
-                InstrumentValueType.DOUBLE));
+                InstrumentValueType.DOUBLE,
+                Advice.empty()));
     MetricDescriptor simpleWithNewDescription =
         MetricDescriptor.create(
             View.builder().build(),
@@ -86,7 +90,8 @@ void testDuplicateExceptionMessage_viewBasedConflict() {
                 "description2",
                 "unit",
                 InstrumentType.HISTOGRAM,
-                InstrumentValueType.DOUBLE));
+                InstrumentValueType.DOUBLE,
+                Advice.empty()));
     assertThat(DebugUtils.duplicateMetricErrorMessage(simple, simpleWithNewDescription))
         .contains("Found duplicate metric definition: name2")
         .contains(simple.getSourceInstrument().getSourceInfo().multiLineDebugString())
@@ -111,7 +116,8 @@ void testDuplicateExceptionMessage_viewBasedConflict2() {
                 "description",
                 "unit2",
                 InstrumentType.HISTOGRAM,
-                InstrumentValueType.DOUBLE));
+                InstrumentValueType.DOUBLE,
+                Advice.empty()));
     MetricDescriptor simpleWithNewDescription =
         MetricDescriptor.create(
             problemView,
@@ -121,7 +127,8 @@ void testDuplicateExceptionMessage_viewBasedConflict2() {
                 "description",
                 "unit",
                 InstrumentType.HISTOGRAM,
-                InstrumentValueType.DOUBLE));
+                InstrumentValueType.DOUBLE,
+                Advice.empty()));
     assertThat(DebugUtils.duplicateMetricErrorMessage(simple, simpleWithNewDescription))
         .contains("Found duplicate metric definition: name")
         .contains("VIEW defined")

sdk/metrics/src/main/java/io/opentelemetry/sdk/metrics/AbstractInstrumentBuilder.java

@@ -9,6 +9,7 @@
 
 import io.opentelemetry.api.metrics.ObservableDoubleMeasurement;
 import io.opentelemetry.api.metrics.ObservableLongMeasurement;
+import io.opentelemetry.sdk.metrics.internal.descriptor.Advice;
 import io.opentelemetry.sdk.metrics.internal.descriptor.InstrumentDescriptor;
 import io.opentelemetry.sdk.metrics.internal.state.CallbackRegistration;
 import io.opentelemetry.sdk.metrics.internal.state.MeterProviderSharedState;
@@ -33,6 +34,7 @@ abstract class AbstractInstrumentBuilder<BuilderT extends AbstractInstrumentBuil
   private final InstrumentValueType valueType;
   private String description;
   private String unit;
+  private Advice advice;
 
   protected final MeterSharedState meterSharedState;
   protected final String instrumentName;
@@ -45,13 +47,34 @@ abstract class AbstractInstrumentBuilder<BuilderT extends AbstractInstrumentBuil
       String name,
       String description,
       String unit) {
+    this(
+        meterProviderSharedState,
+        meterSharedState,
+        type,
+        valueType,
+        name,
+        description,
+        unit,
+        Advice.empty());
+  }
+
+  AbstractInstrumentBuilder(
+      MeterProviderSharedState meterProviderSharedState,
+      MeterSharedState meterSharedState,
+      InstrumentType type,
+      InstrumentValueType valueType,
+      String name,
+      String description,
+      String unit,
+      Advice advice) {
     this.type = type;
     this.valueType = valueType;
     this.instrumentName = name;
     this.description = description;
     this.unit = unit;
     this.meterProviderSharedState = meterProviderSharedState;
     this.meterSharedState = meterSharedState;
+    this.advice = advice;
   }
 
   protected abstract BuilderT getThis();
@@ -74,13 +97,17 @@ public BuilderT setDescription(String description) {
 
   protected <T> T swapBuilder(SwapBuilder<T> swapper) {
     return swapper.newBuilder(
-        meterProviderSharedState, meterSharedState, instrumentName, description, unit);
+        meterProviderSharedState, meterSharedState, instrumentName, description, unit, advice);
+  }
+
+  protected void setAdvice(Advice advice) {
+    this.advice = advice;
   }
 
   final <I extends AbstractInstrument> I buildSynchronousInstrument(
       BiFunction<InstrumentDescriptor, WriteableMetricStorage, I> instrumentFactory) {
     InstrumentDescriptor descriptor =
-        InstrumentDescriptor.create(instrumentName, description, unit, type, valueType);
+        InstrumentDescriptor.create(instrumentName, description, unit, type, valueType, advice);
     WriteableMetricStorage storage =
         meterSharedState.registerSynchronousMetricStorage(descriptor, meterProviderSharedState);
     return instrumentFactory.apply(descriptor, storage);
@@ -108,15 +135,15 @@ final SdkObservableInstrument registerLongAsynchronousInstrument(
 
   final SdkObservableMeasurement buildObservableMeasurement(InstrumentType type) {
     InstrumentDescriptor descriptor =
-        InstrumentDescriptor.create(instrumentName, description, unit, type, valueType);
+        InstrumentDescriptor.create(instrumentName, description, unit, type, valueType, advice);
     return meterSharedState.registerObservableMeasurement(descriptor);
   }
 
   @Override
   public String toString() {
     return this.getClass().getSimpleName()
         + "{descriptor="
-        + InstrumentDescriptor.create(instrumentName, description, unit, type, valueType)
+        + InstrumentDescriptor.create(instrumentName, description, unit, type, valueType, advice)
         + "}";
   }
 
@@ -155,6 +182,7 @@ T newBuilder(
         MeterSharedState meterSharedState,
         String name,
         String description,
-        String unit);
+        String unit,
+        Advice advice);
   }
 }

sdk/metrics/src/main/java/io/opentelemetry/sdk/metrics/SdkDoubleCounter.java

@@ -12,6 +12,7 @@
 import io.opentelemetry.api.metrics.ObservableDoubleMeasurement;
 import io.opentelemetry.context.Context;
 import io.opentelemetry.sdk.internal.ThrottlingLogger;
+import io.opentelemetry.sdk.metrics.internal.descriptor.Advice;
 import io.opentelemetry.sdk.metrics.internal.descriptor.InstrumentDescriptor;
 import io.opentelemetry.sdk.metrics.internal.state.MeterProviderSharedState;
 import io.opentelemetry.sdk.metrics.internal.state.MeterSharedState;
@@ -62,15 +63,17 @@ static final class SdkDoubleCounterBuilder
         MeterSharedState sharedState,
         String name,
         String description,
-        String unit) {
+        String unit,
+        Advice advice) {
       super(
           meterProviderSharedState,
           sharedState,
           InstrumentType.COUNTER,
           InstrumentValueType.DOUBLE,
           name,
           description,
-          unit);
+          unit,
+          advice);
     }
 
     @Override