Add support for createServiceTimeSeries (#318)

* Update export logic for createServiceTimeSeries

* Add test case for use with CreateServiceTimeSeries

* Make serviceTimeSeries builder config public

* Update configuration test

* Switch functional interface to Consumer

exporters/metrics/src/main/java/com/google/cloud/opentelemetry/metric/CloudMetricClient.java

@@ -31,14 +31,24 @@ public interface CloudMetricClient {
   MetricDescriptor createMetricDescriptor(CreateMetricDescriptorRequest request);
 
   /**
-   * Send a timeseries to Cloud Monitoring.
+   * Send a time series to Cloud Monitoring.
    *
-   * @param name The name of the project where we write the timeseries.
-   * @param timeSeries The list of timeseries to write.
-   *     <p>Note: This can only take one point at per timeseries.
+   * @param name The name of the project where we write the time series.
+   * @param timeSeries The list of time series to write.
+   *     <p>Note: This can only take one point at per time series.
    */
   void createTimeSeries(ProjectName name, List<TimeSeries> timeSeries);
 
+  /**
+   * Send a service time series to Cloud Monitoring. A service time series is a time series for a
+   * metric from a Google Cloud service. This method should not be used for sending custom metrics.
+   *
+   * @param name The name of the project where we write the time series.
+   * @param timeSeries The list of time series to write.
+   *     <p>Note: This can only take one point at per time series.
+   */
+  void createServiceTimeSeries(ProjectName name, List<TimeSeries> timeSeries);
+
   /** Shutdown this client, cleaning up any resources. */
   void shutdown();
 }

exporters/metrics/src/main/java/com/google/cloud/opentelemetry/metric/CloudMetricClientImpl.java

@@ -40,6 +40,11 @@ public void createTimeSeries(ProjectName name, List<TimeSeries> timeSeries) {
     this.metricServiceClient.createTimeSeries(name, timeSeries);
   }
 
+  @Override
+  public void createServiceTimeSeries(ProjectName name, List<TimeSeries> timeSeries) {
+    this.metricServiceClient.createServiceTimeSeries(name, timeSeries);
+  }
+
   @Override
   public void shutdown() {
     this.metricServiceClient.shutdown();

exporters/metrics/src/main/java/com/google/cloud/opentelemetry/metric/InternalMetricExporter.java

@@ -45,6 +45,7 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
+import java.util.function.Consumer;
 import java.util.function.Predicate;
 import javax.annotation.Nonnull;
 import org.slf4j.Logger;
@@ -66,18 +67,21 @@ class InternalMetricExporter implements MetricExporter {
   private final String prefix;
   private final MetricDescriptorStrategy metricDescriptorStrategy;
   private final Predicate<AttributeKey<?>> resourceAttributesFilter;
+  private final boolean useCreateServiceTimeSeries;
 
   InternalMetricExporter(
       String projectId,
       String prefix,
       CloudMetricClient client,
       MetricDescriptorStrategy descriptorStrategy,
-      Predicate<AttributeKey<?>> resourceAttributesFilter) {
+      Predicate<AttributeKey<?>> resourceAttributesFilter,
+      boolean useCreateServiceTimeSeries) {
     this.projectId = projectId;
     this.prefix = prefix;
     this.metricServiceClient = client;
     this.metricDescriptorStrategy = descriptorStrategy;
     this.resourceAttributesFilter = resourceAttributesFilter;
+    this.useCreateServiceTimeSeries = useCreateServiceTimeSeries;
   }
 
   static InternalMetricExporter createWithConfiguration(MetricConfiguration configuration)
@@ -115,7 +119,8 @@ static InternalMetricExporter createWithConfiguration(MetricConfiguration config
         prefix,
         new CloudMetricClientImpl(MetricServiceClient.create(builder.build())),
         configuration.getDescriptorStrategy(),
-        configuration.getResourceAttributesFilter());
+        configuration.getResourceAttributesFilter(),
+        configuration.getUseServiceTimeSeries());
   }
 
   @VisibleForTesting
@@ -124,9 +129,15 @@ static InternalMetricExporter createWithClient(
       String prefix,
       CloudMetricClient metricServiceClient,
       MetricDescriptorStrategy descriptorStrategy,
-      Predicate<AttributeKey<?>> resourceAttributesFilter) {
+      Predicate<AttributeKey<?>> resourceAttributesFilter,
+      boolean useCreateServiceTimeSeries) {
     return new InternalMetricExporter(
-        projectId, prefix, metricServiceClient, descriptorStrategy, resourceAttributesFilter);
+        projectId,
+        prefix,
+        metricServiceClient,
+        descriptorStrategy,
+        resourceAttributesFilter,
+        useCreateServiceTimeSeries);
   }
 
   private void exportDescriptor(MetricDescriptor descriptor) {
@@ -197,32 +208,46 @@ public CompletableResultCode export(Collection<MetricData> metrics) {
       // }
     }
     // Update metric descriptors based on configured strategy.
-    try {
-      Collection<MetricDescriptor> descriptors = builder.getDescriptors();
-      if (!descriptors.isEmpty()) {
-        metricDescriptorStrategy.exportDescriptors(descriptors, this::exportDescriptor);
-      }
-    } catch (Exception e) {
-      logger.warn("Failed to create metric descriptors", e);
-    }
+    exportDescriptors(builder);
 
     List<TimeSeries> series = builder.getTimeSeries();
-    createTimeSeriesBatch(metricServiceClient, ProjectName.of(projectId), series);
+    Consumer<List<TimeSeries>> timeSeriesGenerator =
+        timeSeries -> {
+          if (useCreateServiceTimeSeries) {
+            metricServiceClient.createServiceTimeSeries(ProjectName.of(projectId), timeSeries);
+          } else {
+            metricServiceClient.createTimeSeries(ProjectName.of(projectId), timeSeries);
+          }
+        };
+    createTimeSeriesBatch(series, timeSeriesGenerator);
     // TODO: better error reporting.
     if (series.size() < metrics.size()) {
       return CompletableResultCode.ofFailure();
     }
     return CompletableResultCode.ofSuccess();
   }
 
+  private void exportDescriptors(MetricTimeSeriesBuilder timeSeriesBuilder) {
+    if (useCreateServiceTimeSeries) {
+      // do not export metric descriptors when using createServiceTimeSeries
+      return;
+    }
+    try {
+      Collection<MetricDescriptor> descriptors = timeSeriesBuilder.getDescriptors();
+      if (!descriptors.isEmpty()) {
+        metricDescriptorStrategy.exportDescriptors(descriptors, this::exportDescriptor);
+      }
+    } catch (Exception e) {
+      logger.warn("Failed to create metric descriptors", e);
+    }
+  }
+
   // Fragment metrics into batches and send to GCM.
-  private static void createTimeSeriesBatch(
-      CloudMetricClient metricServiceClient,
-      ProjectName projectName,
-      List<TimeSeries> allTimesSeries) {
+  private void createTimeSeriesBatch(
+      List<TimeSeries> allTimesSeries, Consumer<List<TimeSeries>> timeSeriesGenerator) {
     List<List<TimeSeries>> batches = Lists.partition(allTimesSeries, MAX_BATCH_SIZE);
     for (List<TimeSeries> timeSeries : batches) {
-      metricServiceClient.createTimeSeries(projectName, new ArrayList<>(timeSeries));
+      timeSeriesGenerator.accept(new ArrayList<>(timeSeries));
     }
   }
 

exporters/metrics/src/main/java/com/google/cloud/opentelemetry/metric/MetricConfiguration.java

@@ -28,6 +28,7 @@
 import io.opentelemetry.api.common.AttributeKey;
 import io.opentelemetry.semconv.ResourceAttributes;
 import java.time.Duration;
+import java.util.List;
 import java.util.function.Predicate;
 import java.util.function.Supplier;
 import javax.annotation.Nullable;
@@ -141,6 +142,15 @@ public final String getProjectId() {
    */
   public abstract Predicate<AttributeKey<?>> getResourceAttributesFilter();
 
+  /**
+   * Returns a boolean indicating if the {@link MetricConfiguration} is configured to write to a
+   * metric generated from a Google Cloud Service.
+   *
+   * @return true if the {@link MetricConfiguration} is configured to write to a metric generated
+   *     from a Google Cloud Service, false otherwise.
+   */
+  public abstract boolean getUseServiceTimeSeries();
+
   @VisibleForTesting
   abstract boolean getInsecureEndpoint();
 
@@ -164,6 +174,7 @@ public static Builder builder() {
         .setDeadline(DEFAULT_DEADLINE)
         .setDescriptorStrategy(MetricDescriptorStrategy.SEND_ONCE)
         .setInsecureEndpoint(false)
+        .setUseServiceTimeSeries(false)
         .setResourceAttributesFilter(DEFAULT_RESOURCE_ATTRIBUTES_FILTER)
         .setMetricServiceEndpoint(MetricServiceStubSettings.getDefaultEndpoint());
   }
@@ -215,6 +226,18 @@ public final Builder setProjectId(String projectId) {
     /** Sets the endpoint where to write Metrics. Defaults to monitoring.googleapis.com:443. */
     public abstract Builder setMetricServiceEndpoint(String endpoint);
 
+    /**
+     * Sets the {@link MetricConfiguration} to configure the exporter to write metrics via {@link
+     * com.google.cloud.monitoring.v3.MetricServiceClient#createServiceTimeSeries(String, List)}
+     * method. By default, this is false.
+     *
+     * @param useServiceTimeSeries a boolean indicating whether to use {@link
+     *     com.google.cloud.monitoring.v3.MetricServiceClient#createServiceTimeSeries(String, List)}
+     *     method for writing metrics to Google Cloud Monitoring.
+     * @return this
+     */
+    public abstract Builder setUseServiceTimeSeries(boolean useServiceTimeSeries);
+
     /**
      * Set a filter to determine which resource attributes to add to metrics as metric labels. By
      * default, it adds service.name, service.namespace, and service.instance.id. This is

exporters/metrics/src/test/java/com/google/cloud/opentelemetry/metric/FakeData.java

@@ -119,6 +119,16 @@ public class FakeData {
           ImmutableSumData.create(
               true, AggregationTemporality.CUMULATIVE, ImmutableList.of(aLongPoint)));
 
+  static final MetricData googleComputeServiceMetricData =
+      ImmutableMetricData.createLongSum(
+          aGceResource,
+          anInstrumentationLibraryInfo,
+          "guest/disk/io_time",
+          "description",
+          "ns",
+          ImmutableSumData.create(
+              true, AggregationTemporality.CUMULATIVE, ImmutableList.of(aLongPoint)));
+
   static final String aTraceId = "00000000000000000000000000000001";
   static final String aSpanId = "0000000000000002";
   static final SpanContext aSpanContext =

exporters/metrics/src/test/java/com/google/cloud/opentelemetry/metric/GoogleCloudMetricExporterTest.java

@@ -30,6 +30,7 @@
 import static com.google.cloud.opentelemetry.metric.FakeData.aSpanId;
 import static com.google.cloud.opentelemetry.metric.FakeData.aTraceId;
 import static com.google.cloud.opentelemetry.metric.FakeData.anInstrumentationLibraryInfo;
+import static com.google.cloud.opentelemetry.metric.FakeData.googleComputeServiceMetricData;
 import static com.google.cloud.opentelemetry.metric.MetricConfiguration.DEFAULT_PREFIX;
 import static com.google.cloud.opentelemetry.metric.MetricConfiguration.DEFAULT_RESOURCE_ATTRIBUTES_FILTER;
 import static com.google.cloud.opentelemetry.metric.MetricConfiguration.NO_RESOURCE_ATTRIBUTES;
@@ -132,7 +133,8 @@ public void testExportSendsAllDescriptorsOnce() {
             DEFAULT_PREFIX,
             mockClient,
             MetricDescriptorStrategy.SEND_ONCE,
-            DEFAULT_RESOURCE_ATTRIBUTES_FILTER);
+            DEFAULT_RESOURCE_ATTRIBUTES_FILTER,
+            false);
     CompletableResultCode result = exporter.export(ImmutableList.of(aMetricData, aHistogram));
     assertTrue(result.isSuccess());
     CompletableResultCode result2 = exporter.export(ImmutableList.of(aMetricData, aHistogram));
@@ -241,7 +243,8 @@ public void testExportSucceeds() {
             DEFAULT_PREFIX,
             mockClient,
             MetricDescriptorStrategy.ALWAYS_SEND,
-            DEFAULT_RESOURCE_ATTRIBUTES_FILTER);
+            DEFAULT_RESOURCE_ATTRIBUTES_FILTER,
+            false);
 
     CompletableResultCode result = exporter.export(ImmutableList.of(aMetricData));
     verify(mockClient, times(1)).createMetricDescriptor(metricDescriptorCaptor.capture());
@@ -362,7 +365,8 @@ public void testExportWithHistogram_Succeeds() {
             DEFAULT_PREFIX,
             mockClient,
             MetricDescriptorStrategy.ALWAYS_SEND,
-            DEFAULT_RESOURCE_ATTRIBUTES_FILTER);
+            DEFAULT_RESOURCE_ATTRIBUTES_FILTER,
+            false);
     CompletableResultCode result = exporter.export(ImmutableList.of(aHistogram));
     verify(mockClient, times(1)).createMetricDescriptor(metricDescriptorCaptor.capture());
     verify(mockClient, times(1))
@@ -382,7 +386,8 @@ public void testExportWithNonSupportedMetricTypeReturnsFailure() {
             DEFAULT_PREFIX,
             mockClient,
             MetricDescriptorStrategy.ALWAYS_SEND,
-            NO_RESOURCE_ATTRIBUTES);
+            NO_RESOURCE_ATTRIBUTES,
+            false);
 
     MetricData metricData =
         ImmutableMetricData.createDoubleSummary(
@@ -452,6 +457,26 @@ public void verifyExporterCreationErrorDoesNotBreakMetricExporter() {
     }
   }
 
+  @Test
+  public void verifyExporterExportGoogleServiceMetrics() {
+    MetricExporter exporter =
+        InternalMetricExporter.createWithClient(
+            aProjectId,
+            "compute.googleapis.com",
+            mockClient,
+            MetricDescriptorStrategy.ALWAYS_SEND,
+            NO_RESOURCE_ATTRIBUTES,
+            true);
+
+    CompletableResultCode result =
+        exporter.export(ImmutableList.of(googleComputeServiceMetricData));
+    verify(mockClient, times(0)).createMetricDescriptor(any());
+    verify(mockClient, times(0)).createTimeSeries(any(ProjectName.class), any());
+    verify(mockClient, times(1)).createServiceTimeSeries(any(ProjectName.class), any());
+
+    assertTrue(result.isSuccess());
+  }
+
   private void generateOpenTelemetryUsingGoogleCloudMetricExporter(MetricExporter metricExporter) {
     SdkMeterProvider meterProvider =
         SdkMeterProvider.builder()

exporters/metrics/src/test/java/com/google/cloud/opentelemetry/metric/MetricConfigurationTest.java

@@ -16,8 +16,10 @@
 package com.google.cloud.opentelemetry.metric;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertThrows;
+import static org.junit.Assert.assertTrue;
 
 import com.google.auth.Credentials;
 import com.google.auth.oauth2.AccessToken;
@@ -48,6 +50,7 @@ public void testDefaultConfigurationSucceeds() {
 
     assertNull(configuration.getCredentials());
     assertEquals(PROJECT_ID, configuration.getProjectId());
+    assertFalse(configuration.getUseServiceTimeSeries());
   }
 
   @Test
@@ -58,11 +61,13 @@ public void testSetAllConfigurationFieldsSucceeds() {
             .setProjectId(PROJECT_ID)
             .setCredentials(FAKE_CREDENTIALS)
             .setResourceAttributesFilter(allowAllPredicate)
+            .setUseServiceTimeSeries(true)
             .build();
 
     assertEquals(FAKE_CREDENTIALS, configuration.getCredentials());
     assertEquals(PROJECT_ID, configuration.getProjectId());
     assertEquals(allowAllPredicate, configuration.getResourceAttributesFilter());
+    assertTrue(configuration.getUseServiceTimeSeries());
   }
 
   @Test