feat(o11y): introduce gcp.client.repo and gcp.client.artifact attributes (googleapis#4120)

This PR introduces the ability to include repository and artifact name
metadata in generated GAPIC libraries.

## Changes

### GAX (Google API Extensions)
- **`LibraryMetadata`**: Introduced a new internal class to hold
`repository` and `artifactName`.
- **`StubSettings` & `ClientContext`**: Added `LibraryMetadata` to these
classes to carry the metadata through the client lifecycle.
- **Observability/Tracing**: Updated `ApiTracerContext` and
`ObservabilityAttributes` to support these new attributes, enabling them
to be included in exported traces.

### GAPIC Generator
- Support for `repo` and `artifact` flags, passed down to generate a
method in `[Service]StubSettings` that builds an instance of
`LibraryMetadata`.

### Hermetic Build
- Support for `repo` and `artifact` to be passed down to
`generate_library.sh`. The flags reuse the existing logic that
determines the values.

## Verification Results
<img width="1412" height="877" alt="image"
src="https://github.com/user-attachments/assets/1b746361-db2b-4661-bbe6-38f7f63155aa"
/>

## Note on java-bigtable downstream check
Since
[SkipTrailersTest](https://github.com/googleapis/java-bigtable/blob/49fe7692c55747714ada4296ff0f856b1109eba5/google-cloud-bigtable/src/test/java/com/google/cloud/bigtable/data/v2/stub/SkipTrailersTest.java#L97)
mocks the tracer factory, the `EndpointContext` call to
`apiTracerFactory.withContext()` returns a null factory, causing a null
pointer exception when building the client context.
We expect the test to be adjusted with this change with the next
release.

---------

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: cloud-java-bot <cloud-java-bot@google.com>

Author: 3 people

.cloudbuild/library_generation/library_generation.Dockerfile

@@ -30,7 +30,7 @@ RUN cat /java-formatter-version
 RUN V=$(cat /java-formatter-version) && curl -o "/google-java-format.jar" "https://maven-central.storage-download.googleapis.com/maven2/com/google/googlejavaformat/google-java-format/${V}/google-java-format-${V}-all-deps.jar"
 
 # Compile and install packages
-RUN mvn install -B -ntp -DskipTests -Dclirr.skip -Dcheckstyle.skip
+RUN mvn install -B -ntp -T 1.5C -DskipTests -Dcheckstyle.skip -Dclirr.skip -Denforcer.skip -Dfmt.skip
 RUN cp "/root/.m2/repository/com/google/api/gapic-generator-java/${DOCKER_GAPIC_GENERATOR_VERSION}/gapic-generator-java-${DOCKER_GAPIC_GENERATOR_VERSION}.jar" \
   "./gapic-generator-java.jar"
 

gapic-generator-java/src/main/java/com/google/api/generator/gapic/composer/common/AbstractServiceStubSettingsClassComposer.java

@@ -37,6 +37,7 @@
 import com.google.api.gax.rpc.BatchingCallSettings;
 import com.google.api.gax.rpc.BatchingDescriptor;
 import com.google.api.gax.rpc.ClientContext;
+import com.google.api.gax.rpc.LibraryMetadata;
 import com.google.api.gax.rpc.OperationCallSettings;
 import com.google.api.gax.rpc.PageContext;
 import com.google.api.gax.rpc.PagedCallSettings;
@@ -209,6 +210,7 @@ public GapicClass generate(GapicContext context, Service service) {
                     service, serviceConfig, methodSettingsMemberVarExprs, messageTypes, typeStore))
             .setMethods(
                 createClassMethods(
+                    context,
                     service,
                     methodSettingsMemberVarExprs,
                     deprecatedSettingVarNames,
@@ -499,7 +501,6 @@ private static Map<String, VariableExpr> createMethodSettingsClassMemberVarExprs
       boolean isNestedClass,
       Set<String> deprecatedSettingVarNames,
       Set<String> internalSettingVarNames) {
-    // Maintain insertion order.
     Map<String, VariableExpr> varExprs = new LinkedHashMap<>();
 
     // Creates class variables <method>Settings, e.g. echoSettings.
@@ -538,6 +539,7 @@ private static List<Statement> createClassStatements(
       Map<String, VariableExpr> methodSettingsMemberVarExprs,
       Map<String, Message> messageTypes,
       TypeStore typeStore) {
+    // Maintain insertion order.
     Function<Expr, Statement> exprToStatementFn = e -> ExprStatement.withExpr(e);
     List<Statement> statements = new ArrayList<>();
 
@@ -1033,6 +1035,7 @@ private static Expr createPagedListResponseFactoryAssignExpr(
   }
 
   private List<MethodDefinition> createClassMethods(
+      GapicContext context,
       Service service,
       Map<String, VariableExpr> methodSettingsMemberVarExprs,
       Set<String> deprecatedSettingVarNames,
@@ -1053,6 +1056,7 @@ private List<MethodDefinition> createClassMethods(
             SettingsCommentComposer.NEW_BUILDER_METHOD_COMMENT));
     javaMethods.addAll(createBuilderHelperMethods(service, typeStore));
     javaMethods.add(createClassConstructor(service, methodSettingsMemberVarExprs, typeStore));
+    javaMethods.add(createGetLibraryMetadataMethod(context));
     return javaMethods;
   }
 
@@ -2096,6 +2100,48 @@ private static MethodDefinition createNestedClassBuildMethod(
         .build();
   }
 
+  private MethodDefinition createGetLibraryMetadataMethod(GapicContext context) {
+    TypeNode returnType = FIXED_TYPESTORE.get("LibraryMetadata");
+    MethodInvocationExpr libraryMetadataBuilderExpr =
+        MethodInvocationExpr.builder()
+            .setStaticReferenceType(FIXED_TYPESTORE.get("LibraryMetadata"))
+            .setMethodName("newBuilder")
+            .build();
+
+    if (!Strings.isNullOrEmpty(context.artifact())) {
+      libraryMetadataBuilderExpr =
+          MethodInvocationExpr.builder()
+              .setExprReferenceExpr(libraryMetadataBuilderExpr)
+              .setMethodName("setArtifactName")
+              .setArguments(ValueExpr.withValue(StringObjectValue.withValue(context.artifact())))
+              .build();
+    }
+
+    if (!Strings.isNullOrEmpty(context.repo())) {
+      libraryMetadataBuilderExpr =
+          MethodInvocationExpr.builder()
+              .setExprReferenceExpr(libraryMetadataBuilderExpr)
+              .setMethodName("setRepository")
+              .setArguments(ValueExpr.withValue(StringObjectValue.withValue(context.repo())))
+              .build();
+    }
+
+    Expr returnExpr =
+        MethodInvocationExpr.builder()
+            .setExprReferenceExpr(libraryMetadataBuilderExpr)
+            .setMethodName("build")
+            .setReturnType(returnType)
+            .build();
+
+    return MethodDefinition.builder()
+        .setIsOverride(true)
+        .setScope(ScopeNode.PROTECTED)
+        .setReturnType(returnType)
+        .setName("getLibraryMetadata")
+        .setReturnExpr(returnExpr)
+        .build();
+  }
+
   private static TypeStore createStaticTypes() {
     List<Class<?>> concreteClazzes =
         Arrays.asList(
@@ -2121,6 +2167,7 @@ private static TypeStore createStaticTypes() {
             ImmutableMap.class,
             ImmutableSet.class,
             InstantiatingExecutorProvider.class,
+            LibraryMetadata.class,
             LimitExceededBehavior.class,
             List.class,
             Lists.class,

gapic-generator-java/src/main/java/com/google/api/generator/gapic/model/GapicContext.java

@@ -70,6 +70,12 @@ public GapicMetadata gapicMetadata() {
   @Nullable
   public abstract com.google.api.Service serviceYamlProto();
 
+  @Nullable
+  public abstract String repo();
+
+  @Nullable
+  public abstract String artifact();
+
   public boolean containsServices() {
     return !services().isEmpty();
   }
@@ -130,6 +136,10 @@ public Builder setHelperResourceNames(Set<ResourceName> helperResourceNames) {
 
     public abstract Builder setTransport(Transport transport);
 
+    public abstract Builder setRepo(String repo);
+
+    public abstract Builder setArtifact(String artifact);
+
     abstract ImmutableMap<String, ResourceName> resourceNames();
 
     abstract ImmutableMap<String, ResourceName> helperResourceNames();

gapic-generator-java/src/main/java/com/google/api/generator/gapic/protoparser/Parser.java

@@ -150,6 +150,8 @@ public static GapicContext parse(CodeGeneratorRequest request) {
     Optional<GapicLanguageSettings> languageSettingsOpt =
         GapicLanguageSettingsParser.parse(gapicYamlConfigPathOpt);
     Optional<String> transportOpt = PluginArgumentParser.parseTransport(request);
+    Optional<String> repoOpt = PluginArgumentParser.parseRepo(request);
+    Optional<String> artifactOpt = PluginArgumentParser.parseArtifact(request);
 
     boolean willGenerateMetadata = PluginArgumentParser.hasMetadataFlag(request);
     boolean willGenerateNumericEnum = PluginArgumentParser.hasNumericEnumFlag(request);
@@ -253,6 +255,8 @@ public static GapicContext parse(CodeGeneratorRequest request) {
         .setServiceYamlProto(serviceYamlProtoOpt.orElse(null))
         .setTransport(transport)
         .setRestNumericEnumsEnabled(willGenerateNumericEnum)
+        .setRepo(repoOpt.orElse(null))
+        .setArtifact(artifactOpt.orElse(null))
         .build();
   }
 

gapic-generator-java/src/main/java/com/google/api/generator/gapic/protoparser/PluginArgumentParser.java

@@ -32,6 +32,8 @@ public class PluginArgumentParser {
   @VisibleForTesting static final String KEY_NUMERIC_ENUM = "rest-numeric-enums";
   @VisibleForTesting static final String KEY_SERVICE_YAML_CONFIG = "api-service-config";
   @VisibleForTesting static final String KEY_TRANSPORT = "transport";
+  @VisibleForTesting static final String KEY_REPO = "repo";
+  @VisibleForTesting static final String KEY_ARTIFACT = "artifact";
 
   private static final String JSON_FILE_ENDING = "grpc_service_config.json";
   private static final String GAPIC_YAML_FILE_ENDING = "gapic.yaml";
@@ -53,6 +55,14 @@ static Optional<String> parseTransport(CodeGeneratorRequest request) {
     return parseConfigArgument(request.getParameter(), KEY_TRANSPORT);
   }
 
+  static Optional<String> parseRepo(CodeGeneratorRequest request) {
+    return parseConfigArgument(request.getParameter(), KEY_REPO);
+  }
+
+  static Optional<String> parseArtifact(CodeGeneratorRequest request) {
+    return parseConfigArgument(request.getParameter(), KEY_ARTIFACT);
+  }
+
   static boolean hasMetadataFlag(CodeGeneratorRequest request) {
     return hasFlag(request.getParameter(), KEY_METADATA);
   }

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

@@ -11,6 +11,7 @@ import com.google.api.gax.grpc.InstantiatingGrpcChannelProvider;
 import com.google.api.gax.retrying.RetrySettings;
 import com.google.api.gax.rpc.ApiClientHeaderProvider;
 import com.google.api.gax.rpc.ClientContext;
+import com.google.api.gax.rpc.LibraryMetadata;
 import com.google.api.gax.rpc.StatusCode;
 import com.google.api.gax.rpc.StubSettings;
 import com.google.api.gax.rpc.TransportChannelProvider;
@@ -166,6 +167,11 @@ public class EchoWithVersionStubSettings extends StubSettings<EchoWithVersionStu
     echoWithVersionMethodSettings = settingsBuilder.echoWithVersionMethodSettings().build();
   }
 
+  @Override
+  protected LibraryMetadata getLibraryMetadata() {
+    return LibraryMetadata.newBuilder().build();
+  }
+
   /** Builder for EchoWithVersionStubSettings. */
   public static class Builder extends StubSettings.Builder<EchoWithVersionStubSettings, Builder> {
     private final ImmutableList<UnaryCallSettings.Builder<?, ?>> unaryMethodSettingsBuilders;

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

@@ -11,6 +11,7 @@ import com.google.api.gax.grpc.InstantiatingGrpcChannelProvider;
 import com.google.api.gax.retrying.RetrySettings;
 import com.google.api.gax.rpc.ApiClientHeaderProvider;
 import com.google.api.gax.rpc.ClientContext;
+import com.google.api.gax.rpc.LibraryMetadata;
 import com.google.api.gax.rpc.StatusCode;
 import com.google.api.gax.rpc.StubSettings;
 import com.google.api.gax.rpc.TransportChannelProvider;
@@ -183,6 +184,11 @@ public class DeprecatedServiceStubSettings extends StubSettings<DeprecatedServic
     slowFibonacciSettings = settingsBuilder.slowFibonacciSettings().build();
   }
 
+  @Override
+  protected LibraryMetadata getLibraryMetadata() {
+    return LibraryMetadata.newBuilder().build();
+  }
+
   /** Builder for DeprecatedServiceStubSettings. */
   public static class Builder extends StubSettings.Builder<DeprecatedServiceStubSettings, Builder> {
     private final ImmutableList<UnaryCallSettings.Builder<?, ?>> unaryMethodSettingsBuilders;

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

@@ -13,6 +13,7 @@ import com.google.api.gax.grpc.InstantiatingGrpcChannelProvider;
 import com.google.api.gax.retrying.RetrySettings;
 import com.google.api.gax.rpc.ApiClientHeaderProvider;
 import com.google.api.gax.rpc.ClientContext;
+import com.google.api.gax.rpc.LibraryMetadata;
 import com.google.api.gax.rpc.StatusCode;
 import com.google.api.gax.rpc.StreamingCallSettings;
 import com.google.api.gax.rpc.StubSettings;
@@ -220,6 +221,11 @@ public class EchoServiceShouldGeneratePartialUsualStubSettings
         settingsBuilder.echoShouldGenerateAsInternalSettings().build();
   }
 
+  @Override
+  protected LibraryMetadata getLibraryMetadata() {
+    return LibraryMetadata.newBuilder().build();
+  }
+
   /** Builder for EchoServiceShouldGeneratePartialUsualStubSettings. */
   public static class Builder
       extends StubSettings.Builder<EchoServiceShouldGeneratePartialUsualStubSettings, Builder> {

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

@@ -20,6 +20,7 @@ import com.google.api.gax.retrying.RetrySettings;
 import com.google.api.gax.rpc.ApiCallContext;
 import com.google.api.gax.rpc.ApiClientHeaderProvider;
 import com.google.api.gax.rpc.ClientContext;
+import com.google.api.gax.rpc.LibraryMetadata;
 import com.google.api.gax.rpc.OperationCallSettings;
 import com.google.api.gax.rpc.PageContext;
 import com.google.api.gax.rpc.PagedCallSettings;
@@ -406,6 +407,14 @@ public class EchoStubSettings extends StubSettings<EchoStubSettings> {
     pagedExpandLegacySettings = settingsBuilder.pagedExpandLegacySettings().build();
   }
 
+  @Override
+  protected LibraryMetadata getLibraryMetadata() {
+    return LibraryMetadata.newBuilder()
+        .setArtifactName("com.google.cloud:gapic-showcase")
+        .setRepository("googleapis/sdk-platform-java")
+        .build();
+  }
+
   /** Builder for EchoStubSettings. */
   public static class Builder extends StubSettings.Builder<EchoStubSettings, Builder> {
     private final ImmutableList<UnaryCallSettings.Builder<?, ?>> unaryMethodSettingsBuilders;

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

@@ -15,6 +15,7 @@ import com.google.api.gax.retrying.RetrySettings;
 import com.google.api.gax.rpc.ApiCallContext;
 import com.google.api.gax.rpc.ApiClientHeaderProvider;
 import com.google.api.gax.rpc.ClientContext;
+import com.google.api.gax.rpc.LibraryMetadata;
 import com.google.api.gax.rpc.PageContext;
 import com.google.api.gax.rpc.PagedCallSettings;
 import com.google.api.gax.rpc.PagedListDescriptor;
@@ -256,6 +257,11 @@ public class JobServiceStubSettings extends StubSettings<JobServiceStubSettings>
     listJobsSettings = settingsBuilder.listJobsSettings().build();
   }
 
+  @Override
+  protected LibraryMetadata getLibraryMetadata() {
+    return LibraryMetadata.newBuilder().build();
+  }
+
   /** Builder for JobServiceStubSettings. */
   public static class Builder extends StubSettings.Builder<JobServiceStubSettings, Builder> {
     private final ImmutableList<UnaryCallSettings.Builder<?, ?>> unaryMethodSettingsBuilders;