feat: Set sampledToLocalTracing flag to true for all gRPC MethodDescriptors (#3874)

See b/416626151 for more information.

Problem: When the sampledToLocalTracing is set to false or not set, the
gRPC specific metrics have the `grpc.method` attribute defined as
`other` instead of the methodDescriptor's full name. This may be
confusing to customers who may expect to see the full gRPC method name.

High Level: This flag enables captures for specific method names to help
provide more detailed metrics. We do not expect any noticeable
performance impact from this change.

This does not impact the method name that is already properly captured
for Gax Metrics (e.g. Attempt Count, Operation Latency, etc).
Specifically, the use must be using grpc-java telemetry module and be
using
[GrpcOpenTelemetry](https://grpc.github.io/grpc-java/javadoc/io/grpc/opentelemetry/GrpcOpenTelemetry.html)
instead of
[OpenTelemetry](https://github.com/open-telemetry/opentelemetry-java/blob/main/api/all/src/main/java/io/opentelemetry/api/OpenTelemetry.java).

---------

Co-authored-by: cloud-java-bot <[email protected]>

Author: lqiu96

gapic-generator-java/src/main/java/com/google/api/generator/gapic/composer/grpc/GrpcServiceStubClassComposer.java

@@ -22,6 +22,7 @@
 import com.google.api.generator.engine.ast.Expr;
 import com.google.api.generator.engine.ast.ExprStatement;
 import com.google.api.generator.engine.ast.MethodInvocationExpr;
+import com.google.api.generator.engine.ast.PrimitiveValue;
 import com.google.api.generator.engine.ast.ScopeNode;
 import com.google.api.generator.engine.ast.Statement;
 import com.google.api.generator.engine.ast.StringObjectValue;
@@ -140,6 +141,16 @@ protected Statement createMethodDescriptorVariableDecl(
             .apply("setResponseMarshaller", protoUtilsMarshallerFn.apply(methodInvocationArg))
             .apply(methodDescriptorMaker);
 
+    // The sampledToLocalTracing flag is set to true for all gRPC MethodDescriptors in GAPICs
+    // This flag enables captures for specific method names to help provide more detailed metrics
+    methodDescriptorMaker =
+        methodMakerFn
+            .apply(
+                "setSampledToLocalTracing",
+                ValueExpr.withValue(
+                    PrimitiveValue.builder().setType(TypeNode.BOOLEAN).setValue("true").build()))
+            .apply(methodDescriptorMaker);
+
     methodDescriptorMaker =
         MethodInvocationExpr.builder()
             .setMethodName("build")

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/GrpcAutoPopulateFieldStub.golden

@@ -42,6 +42,7 @@ public class GrpcAutoPopulateFieldTestingStub extends AutoPopulateFieldTestingSt
                   ProtoUtils.marshaller(AutoPopulateFieldTestingEchoRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(AutoPopulateFieldTestingEchoResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<
@@ -57,6 +58,7 @@ public class GrpcAutoPopulateFieldTestingStub extends AutoPopulateFieldTestingSt
                   ProtoUtils.marshaller(AutoPopulateFieldTestingExpandRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(AutoPopulateFieldTestingEchoResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<
@@ -72,6 +74,7 @@ public class GrpcAutoPopulateFieldTestingStub extends AutoPopulateFieldTestingSt
                   ProtoUtils.marshaller(AutoPopulateFieldTestingEchoRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(AutoPopulateFieldTestingEchoResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<
@@ -87,6 +90,7 @@ public class GrpcAutoPopulateFieldTestingStub extends AutoPopulateFieldTestingSt
                   ProtoUtils.marshaller(AutoPopulateFieldTestingEchoRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(AutoPopulateFieldTestingEchoResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private final UnaryCallable<

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/GrpcBigQueryJobServiceStub.golden

@@ -35,6 +35,7 @@ public class GrpcJobServiceStub extends JobServiceStub {
               .setRequestMarshaller(
                   ProtoUtils.marshaller(JobProto.DeleteJobRequest.getDefaultInstance()))
               .setResponseMarshaller(ProtoUtils.marshaller(Empty.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<JobProto.ListJobsRequest, JobProto.JobList>
@@ -45,6 +46,7 @@ public class GrpcJobServiceStub extends JobServiceStub {
               .setRequestMarshaller(
                   ProtoUtils.marshaller(JobProto.ListJobsRequest.getDefaultInstance()))
               .setResponseMarshaller(ProtoUtils.marshaller(JobProto.JobList.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private final UnaryCallable<JobProto.DeleteJobRequest, Empty> deleteJobCallable;

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/GrpcCallableNameTypeStub.golden

@@ -33,6 +33,7 @@ public class GrpcCallableNameTypeServiceStub extends CallableNameTypeServiceStub
               .setRequestMarshaller(
                   ProtoUtils.marshaller(GetApiOperationRequest.getDefaultInstance()))
               .setResponseMarshaller(ProtoUtils.marshaller(ApiOperation.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<GetApiOperationRequest, ApiOperation>
@@ -43,6 +44,7 @@ public class GrpcCallableNameTypeServiceStub extends CallableNameTypeServiceStub
               .setRequestMarshaller(
                   ProtoUtils.marshaller(GetApiOperationRequest.getDefaultInstance()))
               .setResponseMarshaller(ProtoUtils.marshaller(ApiOperation.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private final UnaryCallable<GetApiOperationRequest, ApiOperation> getApiOperationCallable;

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/GrpcDeprecatedServiceStub.golden

@@ -32,6 +32,7 @@ public class GrpcDeprecatedServiceStub extends DeprecatedServiceStub {
           .setFullMethodName("google.testdata.v1.DeprecatedService/FastFibonacci")
           .setRequestMarshaller(ProtoUtils.marshaller(FibonacciRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(Empty.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<FibonacciRequest, Empty> slowFibonacciMethodDescriptor =
@@ -40,6 +41,7 @@ public class GrpcDeprecatedServiceStub extends DeprecatedServiceStub {
           .setFullMethodName("google.testdata.v1.DeprecatedService/SlowFibonacci")
           .setRequestMarshaller(ProtoUtils.marshaller(FibonacciRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(Empty.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private final UnaryCallable<FibonacciRequest, Empty> fastFibonacciCallable;

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/GrpcEchoStub.golden

@@ -49,6 +49,7 @@ public class GrpcEchoStub extends EchoStub {
           .setFullMethodName("google.showcase.v1beta1.Echo/Echo")
           .setRequestMarshaller(ProtoUtils.marshaller(EchoRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(EchoResponse.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<ExpandRequest, EchoResponse> expandMethodDescriptor =
@@ -57,6 +58,7 @@ public class GrpcEchoStub extends EchoStub {
           .setFullMethodName("google.showcase.v1beta1.Echo/Expand")
           .setRequestMarshaller(ProtoUtils.marshaller(ExpandRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(EchoResponse.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<EchoRequest, EchoResponse> collectMethodDescriptor =
@@ -65,6 +67,7 @@ public class GrpcEchoStub extends EchoStub {
           .setFullMethodName("google.showcase.v1beta1.Echo/Collect")
           .setRequestMarshaller(ProtoUtils.marshaller(EchoRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(EchoResponse.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<EchoRequest, EchoResponse> chatMethodDescriptor =
@@ -73,6 +76,7 @@ public class GrpcEchoStub extends EchoStub {
           .setFullMethodName("google.showcase.v1beta1.Echo/Chat")
           .setRequestMarshaller(ProtoUtils.marshaller(EchoRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(EchoResponse.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<EchoRequest, EchoResponse> chatAgainMethodDescriptor =
@@ -81,6 +85,7 @@ public class GrpcEchoStub extends EchoStub {
           .setFullMethodName("google.showcase.v1beta1.Echo/ChatAgain")
           .setRequestMarshaller(ProtoUtils.marshaller(EchoRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(EchoResponse.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<PagedExpandRequest, PagedExpandResponse>
@@ -91,6 +96,7 @@ public class GrpcEchoStub extends EchoStub {
               .setRequestMarshaller(ProtoUtils.marshaller(PagedExpandRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(PagedExpandResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<PagedExpandRequest, PagedExpandResponse>
@@ -101,6 +107,7 @@ public class GrpcEchoStub extends EchoStub {
               .setRequestMarshaller(ProtoUtils.marshaller(PagedExpandRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(PagedExpandResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<WaitRequest, Operation> waitMethodDescriptor =
@@ -109,6 +116,7 @@ public class GrpcEchoStub extends EchoStub {
           .setFullMethodName("google.showcase.v1beta1.Echo/Wait")
           .setRequestMarshaller(ProtoUtils.marshaller(WaitRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(Operation.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<BlockRequest, BlockResponse> blockMethodDescriptor =
@@ -117,6 +125,7 @@ public class GrpcEchoStub extends EchoStub {
           .setFullMethodName("google.showcase.v1beta1.Echo/Block")
           .setRequestMarshaller(ProtoUtils.marshaller(BlockRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(BlockResponse.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<EchoRequest, Object> collideNameMethodDescriptor =
@@ -125,6 +134,7 @@ public class GrpcEchoStub extends EchoStub {
           .setFullMethodName("google.showcase.v1beta1.Echo/CollideName")
           .setRequestMarshaller(ProtoUtils.marshaller(EchoRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(Object.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<PagedExpandLegacyRequest, PagedExpandResponse>
@@ -136,6 +146,7 @@ public class GrpcEchoStub extends EchoStub {
                   ProtoUtils.marshaller(PagedExpandLegacyRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(PagedExpandResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private final UnaryCallable<EchoRequest, EchoResponse> echoCallable;

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/GrpcLoggingStub.golden

@@ -46,6 +46,7 @@ public class GrpcLoggingServiceV2Stub extends LoggingServiceV2Stub {
           .setFullMethodName("google.logging.v2.LoggingServiceV2/DeleteLog")
           .setRequestMarshaller(ProtoUtils.marshaller(DeleteLogRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(Empty.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<WriteLogEntriesRequest, WriteLogEntriesResponse>
@@ -57,6 +58,7 @@ public class GrpcLoggingServiceV2Stub extends LoggingServiceV2Stub {
                   ProtoUtils.marshaller(WriteLogEntriesRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(WriteLogEntriesResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<ListLogEntriesRequest, ListLogEntriesResponse>
@@ -68,6 +70,7 @@ public class GrpcLoggingServiceV2Stub extends LoggingServiceV2Stub {
                   ProtoUtils.marshaller(ListLogEntriesRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(ListLogEntriesResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<
@@ -85,6 +88,7 @@ public class GrpcLoggingServiceV2Stub extends LoggingServiceV2Stub {
               .setResponseMarshaller(
                   ProtoUtils.marshaller(
                       ListMonitoredResourceDescriptorsResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<ListLogsRequest, ListLogsResponse>
@@ -94,6 +98,7 @@ public class GrpcLoggingServiceV2Stub extends LoggingServiceV2Stub {
               .setFullMethodName("google.logging.v2.LoggingServiceV2/ListLogs")
               .setRequestMarshaller(ProtoUtils.marshaller(ListLogsRequest.getDefaultInstance()))
               .setResponseMarshaller(ProtoUtils.marshaller(ListLogsResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<TailLogEntriesRequest, TailLogEntriesResponse>
@@ -105,6 +110,7 @@ public class GrpcLoggingServiceV2Stub extends LoggingServiceV2Stub {
                   ProtoUtils.marshaller(TailLogEntriesRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(TailLogEntriesResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private final UnaryCallable<DeleteLogRequest, Empty> deleteLogCallable;

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/grpc/goldens/GrpcPublisherStub.golden

@@ -48,6 +48,7 @@ public class GrpcPublisherStub extends PublisherStub {
           .setFullMethodName("google.pubsub.v1.Publisher/CreateTopic")
           .setRequestMarshaller(ProtoUtils.marshaller(Topic.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(Topic.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<UpdateTopicRequest, Topic> updateTopicMethodDescriptor =
@@ -56,6 +57,7 @@ public class GrpcPublisherStub extends PublisherStub {
           .setFullMethodName("google.pubsub.v1.Publisher/UpdateTopic")
           .setRequestMarshaller(ProtoUtils.marshaller(UpdateTopicRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(Topic.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<PublishRequest, PublishResponse> publishMethodDescriptor =
@@ -64,6 +66,7 @@ public class GrpcPublisherStub extends PublisherStub {
           .setFullMethodName("google.pubsub.v1.Publisher/Publish")
           .setRequestMarshaller(ProtoUtils.marshaller(PublishRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(PublishResponse.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<GetTopicRequest, Topic> getTopicMethodDescriptor =
@@ -72,6 +75,7 @@ public class GrpcPublisherStub extends PublisherStub {
           .setFullMethodName("google.pubsub.v1.Publisher/GetTopic")
           .setRequestMarshaller(ProtoUtils.marshaller(GetTopicRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(Topic.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<ListTopicsRequest, ListTopicsResponse>
@@ -81,6 +85,7 @@ public class GrpcPublisherStub extends PublisherStub {
               .setFullMethodName("google.pubsub.v1.Publisher/ListTopics")
               .setRequestMarshaller(ProtoUtils.marshaller(ListTopicsRequest.getDefaultInstance()))
               .setResponseMarshaller(ProtoUtils.marshaller(ListTopicsResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<
@@ -94,6 +99,7 @@ public class GrpcPublisherStub extends PublisherStub {
                   ProtoUtils.marshaller(ListTopicSubscriptionsRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(ListTopicSubscriptionsResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<ListTopicSnapshotsRequest, ListTopicSnapshotsResponse>
@@ -105,6 +111,7 @@ public class GrpcPublisherStub extends PublisherStub {
                   ProtoUtils.marshaller(ListTopicSnapshotsRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(ListTopicSnapshotsResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private static final MethodDescriptor<DeleteTopicRequest, Empty> deleteTopicMethodDescriptor =
@@ -113,6 +120,7 @@ public class GrpcPublisherStub extends PublisherStub {
           .setFullMethodName("google.pubsub.v1.Publisher/DeleteTopic")
           .setRequestMarshaller(ProtoUtils.marshaller(DeleteTopicRequest.getDefaultInstance()))
           .setResponseMarshaller(ProtoUtils.marshaller(Empty.getDefaultInstance()))
+          .setSampledToLocalTracing(true)
           .build();
 
   private static final MethodDescriptor<DetachSubscriptionRequest, DetachSubscriptionResponse>
@@ -124,6 +132,7 @@ public class GrpcPublisherStub extends PublisherStub {
                   ProtoUtils.marshaller(DetachSubscriptionRequest.getDefaultInstance()))
               .setResponseMarshaller(
                   ProtoUtils.marshaller(DetachSubscriptionResponse.getDefaultInstance()))
+              .setSampledToLocalTracing(true)
               .build();
 
   private final UnaryCallable<Topic, Topic> createTopicCallable;