Added DelegatingMetricData & TestMetricData Classes

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

@@ -1,2 +1,15 @@
 Comparing source compatibility of  against 
-No changes.
++++  NEW CLASS: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.metrics.data.DelegatingMetricData  (not serializable)
+	+++  CLASS FILE FORMAT VERSION: 52.0 <- n.a.
+	+++  NEW INTERFACE: io.opentelemetry.sdk.metrics.data.MetricData
+	+++  NEW SUPERCLASS: java.lang.Object
+	+++  NEW METHOD: PUBLIC(+) boolean equals(java.lang.Object)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.data.Data<?> getData()
+	+++  NEW METHOD: PUBLIC(+) java.lang.String getDescription()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.common.InstrumentationScopeInfo getInstrumentationScopeInfo()
+	+++  NEW METHOD: PUBLIC(+) java.lang.String getName()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.resources.Resource getResource()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.data.MetricDataType getType()
+	+++  NEW METHOD: PUBLIC(+) java.lang.String getUnit()
+	+++  NEW METHOD: PUBLIC(+) int hashCode()
+	+++  NEW METHOD: PUBLIC(+) java.lang.String toString()

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

@@ -1,2 +1,18 @@
 Comparing source compatibility of  against 
-No changes.
++++  NEW CLASS: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.testing.metrics.TestMetricData  (not serializable)
+	+++  CLASS FILE FORMAT VERSION: 52.0 <- n.a.
+	+++  NEW SUPERCLASS: java.lang.Object
+	+++  NEW CONSTRUCTOR: PUBLIC(+) TestMetricData()
+	+++  NEW METHOD: PUBLIC(+) STATIC(+) io.opentelemetry.sdk.testing.metrics.TestMetricData$Builder builder()
++++  NEW CLASS: PUBLIC(+) ABSTRACT(+) STATIC(+) io.opentelemetry.sdk.testing.metrics.TestMetricData$Builder  (not serializable)
+	+++  CLASS FILE FORMAT VERSION: 52.0 <- n.a.
+	+++  NEW SUPERCLASS: java.lang.Object
+	+++  NEW CONSTRUCTOR: PUBLIC(+) TestMetricData$Builder()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.metrics.TestMetricData build()
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.testing.metrics.TestMetricData$Builder setData(io.opentelemetry.sdk.metrics.data.Data<?>)
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.testing.metrics.TestMetricData$Builder setDescription(java.lang.String)
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.testing.metrics.TestMetricData$Builder setInstrumentationScopeInfo(io.opentelemetry.sdk.common.InstrumentationScopeInfo)
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.testing.metrics.TestMetricData$Builder setName(java.lang.String)
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.testing.metrics.TestMetricData$Builder setResource(io.opentelemetry.sdk.resources.Resource)
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.testing.metrics.TestMetricData$Builder setType(io.opentelemetry.sdk.metrics.data.MetricDataType)
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.testing.metrics.TestMetricData$Builder setUnit(java.lang.String)

sdk/metrics/src/main/java/io/opentelemetry/sdk/metrics/data/DelegatingMetricData.java

@@ -0,0 +1,124 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.sdk.metrics.data;
+
+import static java.util.Objects.requireNonNull;
+
+import io.opentelemetry.sdk.common.InstrumentationScopeInfo;
+import io.opentelemetry.sdk.resources.Resource;
+import javax.annotation.Nullable;
+
+/**
+ * A {@link MetricData} which delegates all methods to another {@link MetricData}. Extend this class
+ * to modify the {@link MetricData} that will be exported.
+ */
+public abstract class DelegatingMetricData implements MetricData {
+
+  private final MetricData delegate;
+
+  protected DelegatingMetricData(MetricData delegate) {
+    this.delegate = requireNonNull(delegate, "delegate");
+  }
+
+  @Override
+  public Resource getResource() {
+    return delegate.getResource();
+  }
+
+  @Override
+  public InstrumentationScopeInfo getInstrumentationScopeInfo() {
+    return delegate.getInstrumentationScopeInfo();
+  }
+
+  @Override
+  public String getName() {
+    return delegate.getName();
+  }
+
+  @Override
+  public String getDescription() {
+    return delegate.getDescription();
+  }
+
+  @Override
+  public String getUnit() {
+    return delegate.getUnit();
+  }
+
+  @Override
+  public MetricDataType getType() {
+    return delegate.getType();
+  }
+
+  @Override
+  public Data<?> getData() {
+    return delegate.getData();
+  }
+
+  @Override
+  public boolean equals(@Nullable Object o) {
+    if (o == this) {
+      return true;
+    }
+    if (o instanceof MetricData) {
+      MetricData that = (MetricData) o;
+      return getResource().equals(that.getResource())
+          && getInstrumentationScopeInfo().equals(that.getInstrumentationScopeInfo())
+          && getName().equals(that.getName())
+          && getDescription().equals(that.getDescription())
+          && getUnit().equals(that.getUnit())
+          && getType().equals(that.getType())
+          && getData().equals(that.getData());
+    }
+    return false;
+  }
+
+  @Override
+  public int hashCode() {
+    int result = 1;
+    result *= 1000003;
+    result ^= this.getResource().hashCode();
+    result *= 1000003;
+    result ^= this.getInstrumentationScopeInfo().hashCode();
+    result *= 1000003;
+    result ^= this.getName().hashCode();
+    result *= 1000003;
+    result ^= this.getDescription().hashCode();
+    result *= 1000003;
+    result ^= this.getUnit().hashCode();
+    result *= 1000003;
+    result ^= this.getType().hashCode();
+    result *= 1000003;
+    result ^= this.getData().hashCode();
+    return result;
+  }
+
+  @Override
+  public String toString() {
+    return "DelegatingMetricData{"
+        + "resource="
+        + getResource()
+        + ", "
+        + "instrumentationScopeInfo="
+        + getInstrumentationScopeInfo()
+        + ", "
+        + "name="
+        + getName()
+        + ", "
+        + "description="
+        + getDescription()
+        + ", "
+        + "unit="
+        + getUnit()
+        + ", "
+        + "type="
+        + getType()
+        + ", "
+        + "data="
+        + getData()
+        + "}";
+  }
+}

sdk/metrics/src/test/java/io/opentelemetry/sdk/metrics/data/DelegatingMetricDataTest.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.sdk.metrics.data;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import io.opentelemetry.sdk.common.InstrumentationScopeInfo;
+import io.opentelemetry.sdk.metrics.internal.data.ImmutableSummaryData;
+import io.opentelemetry.sdk.resources.Resource;
+import io.opentelemetry.sdk.testing.metrics.TestMetricData;
+import org.assertj.core.api.recursive.comparison.RecursiveComparisonConfiguration;
+import org.junit.jupiter.api.Test;
+
+class DelegatingMetricDataTest {
+
+  private static final class NoOpDelegatingMetricData extends DelegatingMetricData {
+    private NoOpDelegatingMetricData(MetricData delegate) {
+      super(delegate);
+    }
+  }
+
+  private static final class MetricDataWithCustomDescription extends DelegatingMetricData {
+    private final String description;
+
+    private MetricDataWithCustomDescription(MetricData delegate) {
+      super(delegate);
+      this.description = "test";
+    }
+
+    @Override
+    public String getDescription() {
+      return description;
+    }
+  }
+
+  @Test
+  void delegates() {
+    MetricData metricData = createBasicMetricBuilder().build();
+    MetricData noOpWrapper = new NoOpDelegatingMetricData(metricData);
+
+    assertThat(noOpWrapper)
+        .usingRecursiveComparison(
+            RecursiveComparisonConfiguration.builder().withIgnoredFields("delegate").build())
+        .isEqualTo(metricData);
+  }
+
+  @Test
+  void overrideDelegate() {
+    MetricData metricData = createBasicMetricBuilder().build();
+    MetricData withCustomDescription = new MetricDataWithCustomDescription(metricData);
+
+    assertThat(withCustomDescription.getDescription()).isEqualTo("test");
+  }
+
+  @Test
+  void equals() {
+    MetricData metricData = createBasicMetricBuilder().build();
+    MetricData noOpWrapper = new NoOpDelegatingMetricData(metricData);
+    MetricData withCustomDescription = new MetricDataWithCustomDescription(metricData);
+
+    assertThat(noOpWrapper).isEqualTo(metricData);
+    assertThat(metricData).isNotEqualTo(withCustomDescription);
+  }
+
+  private static TestMetricData.Builder createBasicMetricBuilder() {
+    return TestMetricData.builder()
+        .setResource(Resource.empty())
+        .setInstrumentationScopeInfo(InstrumentationScopeInfo.empty())
+        .setDescription("")
+        .setUnit("1")
+        .setName("name")
+        .setData(ImmutableSummaryData.empty())
+        .setType(MetricDataType.SUMMARY); // Not sure what type should be here
+  }
+}

sdk/testing/src/main/java/io/opentelemetry/sdk/testing/metrics/TestMetricData.java

@@ -0,0 +1,107 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.sdk.testing.metrics;
+
+import com.google.auto.value.AutoValue;
+import io.opentelemetry.sdk.common.InstrumentationScopeInfo;
+import io.opentelemetry.sdk.metrics.data.Data;
+import io.opentelemetry.sdk.metrics.data.MetricData;
+import io.opentelemetry.sdk.metrics.data.MetricDataType;
+import io.opentelemetry.sdk.metrics.internal.data.ImmutableSummaryData;
+import io.opentelemetry.sdk.resources.Resource;
+import javax.annotation.concurrent.Immutable;
+
+/**
+ * Immutable representation of all data collected by the {@link
+ * io.opentelemetry.sdk.metrics.data.MetricData} class.
+ */
+@Immutable
+@AutoValue
+public abstract class TestMetricData implements MetricData {
+  public static Builder builder() {
+    return new AutoValue_TestMetricData.Builder()
+        .setResource(Resource.empty())
+        .setName("name")
+        .setInstrumentationScopeInfo(InstrumentationScopeInfo.empty())
+        .setDescription("description")
+        .setUnit("1")
+        .setData(ImmutableSummaryData.empty())
+        .setType(MetricDataType.SUMMARY);
+  }
+
+  /** A builder for {@link TestMetricData}. */
+  @AutoValue.Builder
+  public abstract static class Builder {
+    abstract TestMetricData autoBuild();
+
+    /**
+     * Builds and returns a new {@link MetricData} instance from the data in {@code this}.
+     *
+     * @return a new {@link MetricData} instance.
+     */
+    public TestMetricData build() {
+      return autoBuild();
+    }
+
+    /**
+     * Sets the resource of the metric.
+     *
+     * @param resource the resource of the metric.
+     * @return this.
+     */
+    public abstract Builder setResource(Resource resource);
+
+    /**
+     * Sets the name of the metric.
+     *
+     * @param name the name of the metric.
+     * @return this.
+     */
+    public abstract Builder setName(String name);
+
+    /**
+     * Sets the description of the metric.
+     *
+     * @param description the description of the metric.
+     * @return this.
+     */
+    public abstract Builder setDescription(String description);
+
+    /**
+     * Sets the unit of the metric.
+     *
+     * @param unit the unit of the metric.
+     * @return this.
+     */
+    public abstract Builder setUnit(String unit);
+
+    /**
+     * Sets the type of the metric.
+     *
+     * @param type the type of the metric.
+     * @return this.
+     */
+    public abstract Builder setType(MetricDataType type);
+
+    /**
+     * Sets the data of the metric.
+     *
+     * @param data the data of the metric.
+     * @return this.
+     */
+    public abstract Builder setData(Data<?> data);
+
+    /**
+     * Sets the Instrumentation scope of the metric.
+     *
+     * @param instrumentationScopeInfo the instrumentation scope of the tracer which created this
+     *     metric.
+     * @return this.
+     */
+    public abstract Builder setInstrumentationScopeInfo(
+        InstrumentationScopeInfo instrumentationScopeInfo);
+  }
+}