feat: Numeric enums in routing headers

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

@@ -1300,7 +1300,10 @@ private void createRequestParamsExtractorBodyForHttpBindings(
     for (HttpBindings.HttpBinding httpBindingFieldBinding :
         method.httpBindings().pathParameters()) {
       MethodInvocationExpr requestBuilderExpr =
-          createRequestFieldGetterExpr(requestVarExpr, httpBindingFieldBinding.name());
+          createRequestFieldGetterExpr(
+              requestVarExpr,
+              httpBindingFieldBinding.name(),
+              httpBindingFieldBinding.field() != null && httpBindingFieldBinding.field().isEnum());
       Expr valueOfExpr =
           MethodInvocationExpr.builder()
               .setStaticReferenceType(TypeNode.STRING)
@@ -1360,8 +1363,10 @@ private void createRequestParamsExtractorBodyForRoutingHeaders(
             .build();
     for (int i = 0; i < routingHeaderParams.size(); i++) {
       RoutingHeaderRule.RoutingHeaderParam routingHeaderParam = routingHeaderParams.get(i);
+      // Explicit routing headers are implemented as strings currently, hence sending "false"
+      // in isFieldEnum() for it.
       MethodInvocationExpr requestFieldGetterExpr =
-          createRequestFieldGetterExpr(requestVarExpr, routingHeaderParam.fieldName());
+          createRequestFieldGetterExpr(requestVarExpr, routingHeaderParam.fieldName(), false);
       Expr routingHeaderKeyExpr =
           ValueExpr.withValue(StringObjectValue.withValue(routingHeaderParam.key()));
       String pathTemplateName =
@@ -1462,7 +1467,7 @@ private Expr fieldValuesNotNullConditionExpr(
   }
 
   private MethodInvocationExpr createRequestFieldGetterExpr(
-      VariableExpr requestVarExpr, String fieldName) {
+      VariableExpr requestVarExpr, String fieldName, boolean isFieldEnum) {
     MethodInvocationExpr.Builder requestFieldGetterExprBuilder =
         MethodInvocationExpr.builder().setExprReferenceExpr(requestVarExpr);
     List<String> descendantFields = Splitter.on(".").splitToList(fieldName);
@@ -1472,6 +1477,18 @@ private MethodInvocationExpr createRequestFieldGetterExpr(
       String currFieldName = descendantFields.get(i);
       String bindingFieldMethodName =
           String.format("get%s", JavaStyle.toUpperCamelCase(currFieldName));
+
+      // Only at the last descendant field, if enum, we want to extract the value.
+      // For example, consider the chain request.getFoo().getBar().
+      // If you added "Value" to both fields (getFooValue().getBarValue()),
+      // it would not work correctly, as getFooValue() may return an int or some other type,
+      // and calling getBarValue() on it wouldn't make sense
+      // By adding "Value" only at the last descendant field,
+      // you ensure that the modification aligns with the expected method
+      // chaining behavior and correctly retrieves the underlying value of the enum field."
+      if (i == descendantFields.size() - 1 && isFieldEnum) {
+        bindingFieldMethodName = bindingFieldMethodName + "Value";
+      }
       requestFieldGetterExprBuilder =
           requestFieldGetterExprBuilder.setMethodName(bindingFieldMethodName);
       if (i < descendantFields.size() - 1) {

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

@@ -8,6 +8,8 @@ import com.google.api.gax.rpc.ClientContext;
 import com.google.api.gax.rpc.RequestParamsBuilder;
 import com.google.api.gax.rpc.UnaryCallable;
 import com.google.api.pathtemplate.PathTemplate;
+import com.google.explicit.dynamic.routing.header.EnumRequest;
+import com.google.explicit.dynamic.routing.header.EnumResponse;
 import com.google.explicit.dynamic.routing.header.Request;
 import com.google.explicit.dynamic.routing.header.RequestWithNestedField;
 import com.google.longrunning.stub.GrpcOperationsStub;
@@ -156,6 +158,16 @@ public class GrpcExplicitDynamicRoutingHeaderTestingStub
               .setResponseMarshaller(ProtoUtils.marshaller(Empty.getDefaultInstance()))
               .build();
 
+  private static final MethodDescriptor<EnumRequest, EnumResponse>
+      implicitRoutingHeaderWithEnumTestMethodDescriptor =
+          MethodDescriptor.<EnumRequest, EnumResponse>newBuilder()
+              .setType(MethodDescriptor.MethodType.UNARY)
+              .setFullMethodName(
+                  "google.explicit.dynamic.routing.header.ExplicitDynamicRoutingHeaderTesting/ImplicitRoutingHeaderWithEnumTest")
+              .setRequestMarshaller(ProtoUtils.marshaller(EnumRequest.getDefaultInstance()))
+              .setResponseMarshaller(ProtoUtils.marshaller(EnumResponse.getDefaultInstance()))
+              .build();
+
   private final UnaryCallable<Request, Empty> example1TestCallable;
   private final UnaryCallable<Request, Empty> example2TestCallable;
   private final UnaryCallable<Request, Empty> example3TestCallable;
@@ -170,6 +182,7 @@ public class GrpcExplicitDynamicRoutingHeaderTestingStub
   private final UnaryCallable<Request, Empty> backwardsCompatible2TestCallable;
   private final UnaryCallable<Request, Empty> backwardsCompatible3TestCallable;
   private final UnaryCallable<RequestWithNestedField, Empty> nestedFieldTestCallable;
+  private final UnaryCallable<EnumRequest, EnumResponse> implicitRoutingHeaderWithEnumTestCallable;
 
   private final BackgroundResource backgroundResources;
   private final GrpcOperationsStub operationsStub;
@@ -427,6 +440,17 @@ public class GrpcExplicitDynamicRoutingHeaderTestingStub
                   return builder.build();
                 })
             .build();
+    GrpcCallSettings<EnumRequest, EnumResponse> implicitRoutingHeaderWithEnumTestTransportSettings =
+        GrpcCallSettings.<EnumRequest, EnumResponse>newBuilder()
+            .setMethodDescriptor(implicitRoutingHeaderWithEnumTestMethodDescriptor)
+            .setParamsExtractor(
+                request -> {
+                  RequestParamsBuilder builder = RequestParamsBuilder.create();
+                  builder.add(
+                      "info.enum_test", String.valueOf(request.getInfo().getEnumTestValue()));
+                  return builder.build();
+                })
+            .build();
 
     this.example1TestCallable =
         callableFactory.createUnaryCallable(
@@ -476,6 +500,11 @@ public class GrpcExplicitDynamicRoutingHeaderTestingStub
     this.nestedFieldTestCallable =
         callableFactory.createUnaryCallable(
             nestedFieldTestTransportSettings, settings.nestedFieldTestSettings(), clientContext);
+    this.implicitRoutingHeaderWithEnumTestCallable =
+        callableFactory.createUnaryCallable(
+            implicitRoutingHeaderWithEnumTestTransportSettings,
+            settings.implicitRoutingHeaderWithEnumTestSettings(),
+            clientContext);
 
     this.backgroundResources =
         new BackgroundResourceAggregation(clientContext.getBackgroundResources());
@@ -555,6 +584,11 @@ public class GrpcExplicitDynamicRoutingHeaderTestingStub
     return nestedFieldTestCallable;
   }
 
+  @Override
+  public UnaryCallable<EnumRequest, EnumResponse> implicitRoutingHeaderWithEnumTestCallable() {
+    return implicitRoutingHeaderWithEnumTestCallable;
+  }
+
   @Override
   public final void close() {
     try {

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

@@ -266,7 +266,7 @@ public class GrpcTestingStub extends TestingStub {
                   builder.add("name", String.valueOf(request.getName()));
                   builder.add(
                       "test_to_verify.name", String.valueOf(request.getTestToVerify().getName()));
-                  builder.add("type", String.valueOf(request.getType()));
+                  builder.add("type", String.valueOf(request.getTypeValue()));
                   return builder.build();
                 })
             .build();

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/rest/goldens/HttpJsonComplianceStub.golden

@@ -426,7 +426,8 @@ public class HttpJsonComplianceStub extends ComplianceStub {
                   builder.add("info.f_bool", String.valueOf(request.getInfo().getFBool()));
                   builder.add("info.f_double", String.valueOf(request.getInfo().getFDouble()));
                   builder.add("info.f_int32", String.valueOf(request.getInfo().getFInt32()));
-                  builder.add("info.f_kingdom", String.valueOf(request.getInfo().getFKingdom()));
+                  builder.add(
+                      "info.f_kingdom", String.valueOf(request.getInfo().getFKingdomValue()));
                   builder.add("info.f_string", String.valueOf(request.getInfo().getFString()));
                   return builder.build();
                 })

gapic-generator-java/src/test/java/com/google/api/generator/gapic/composer/rest/goldens/HttpJsonRoutingHeadersStub.golden

@@ -14,6 +14,8 @@ import com.google.api.gax.rpc.ClientContext;
 import com.google.api.gax.rpc.RequestParamsBuilder;
 import com.google.api.gax.rpc.UnaryCallable;
 import com.google.api.pathtemplate.PathTemplate;
+import com.google.explicit.dynamic.routing.header.EnumRequest;
+import com.google.explicit.dynamic.routing.header.EnumResponse;
 import com.google.explicit.dynamic.routing.header.Request;
 import com.google.explicit.dynamic.routing.header.RequestWithNestedField;
 import com.google.protobuf.Empty;
@@ -140,9 +142,48 @@ public class HttpJsonExplicitDynamicRoutingHeaderTestingStub
                       .build())
               .build();
 
+  private static final ApiMethodDescriptor<EnumRequest, EnumResponse>
+      implicitRoutingHeaderWithEnumTestMethodDescriptor =
+          ApiMethodDescriptor.<EnumRequest, EnumResponse>newBuilder()
+              .setFullMethodName(
+                  "google.explicit.dynamic.routing.header.ExplicitDynamicRoutingHeaderTesting/ImplicitRoutingHeaderWithEnumTest")
+              .setHttpMethod("POST")
+              .setType(ApiMethodDescriptor.MethodType.UNARY)
+              .setRequestFormatter(
+                  ProtoMessageRequestFormatter.<EnumRequest>newBuilder()
+                      .setPath(
+                          "/v1beta1/{info.enumTest}",
+                          request -> {
+                            Map<String, String> fields = new HashMap<>();
+                            ProtoRestSerializer<EnumRequest> serializer =
+                                ProtoRestSerializer.create();
+                            serializer.putPathParam(
+                                fields, "info.enumTest", request.getInfo().getEnumTestValue());
+                            return fields;
+                          })
+                      .setQueryParamsExtractor(
+                          request -> {
+                            Map<String, List<String>> fields = new HashMap<>();
+                            ProtoRestSerializer<EnumRequest> serializer =
+                                ProtoRestSerializer.create();
+                            return fields;
+                          })
+                      .setRequestBodyExtractor(
+                          request ->
+                              ProtoRestSerializer.create()
+                                  .toBody("*", request.toBuilder().build(), false))
+                      .build())
+              .setResponseParser(
+                  ProtoMessageResponseParser.<EnumResponse>newBuilder()
+                      .setDefaultInstance(EnumResponse.getDefaultInstance())
+                      .setDefaultTypeRegistry(typeRegistry)
+                      .build())
+              .build();
+
   private final UnaryCallable<Request, Empty> backwardsCompatible1TestCallable;
   private final UnaryCallable<Request, Empty> backwardsCompatible2TestCallable;
   private final UnaryCallable<Request, Empty> backwardsCompatible3TestCallable;
+  private final UnaryCallable<EnumRequest, EnumResponse> implicitRoutingHeaderWithEnumTestCallable;
 
   private final BackgroundResource backgroundResources;
   private final HttpJsonStubCallableFactory callableFactory;
@@ -223,6 +264,19 @@ public class HttpJsonExplicitDynamicRoutingHeaderTestingStub
                   return builder.build();
                 })
             .build();
+    HttpJsonCallSettings<EnumRequest, EnumResponse>
+        implicitRoutingHeaderWithEnumTestTransportSettings =
+            HttpJsonCallSettings.<EnumRequest, EnumResponse>newBuilder()
+                .setMethodDescriptor(implicitRoutingHeaderWithEnumTestMethodDescriptor)
+                .setTypeRegistry(typeRegistry)
+                .setParamsExtractor(
+                    request -> {
+                      RequestParamsBuilder builder = RequestParamsBuilder.create();
+                      builder.add(
+                          "info.enum_test", String.valueOf(request.getInfo().getEnumTestValue()));
+                      return builder.build();
+                    })
+                .build();
 
     this.backwardsCompatible1TestCallable =
         callableFactory.createUnaryCallable(
@@ -239,6 +293,11 @@ public class HttpJsonExplicitDynamicRoutingHeaderTestingStub
             backwardsCompatible3TestTransportSettings,
             settings.backwardsCompatible3TestSettings(),
             clientContext);
+    this.implicitRoutingHeaderWithEnumTestCallable =
+        callableFactory.createUnaryCallable(
+            implicitRoutingHeaderWithEnumTestTransportSettings,
+            settings.implicitRoutingHeaderWithEnumTestSettings(),
+            clientContext);
 
     this.backgroundResources =
         new BackgroundResourceAggregation(clientContext.getBackgroundResources());
@@ -250,6 +309,7 @@ public class HttpJsonExplicitDynamicRoutingHeaderTestingStub
     methodDescriptors.add(backwardsCompatible1TestMethodDescriptor);
     methodDescriptors.add(backwardsCompatible2TestMethodDescriptor);
     methodDescriptors.add(backwardsCompatible3TestMethodDescriptor);
+    methodDescriptors.add(implicitRoutingHeaderWithEnumTestMethodDescriptor);
     return methodDescriptors;
   }
 
@@ -268,6 +328,11 @@ public class HttpJsonExplicitDynamicRoutingHeaderTestingStub
     return backwardsCompatible3TestCallable;
   }
 
+  @Override
+  public UnaryCallable<EnumRequest, EnumResponse> implicitRoutingHeaderWithEnumTestCallable() {
+    return implicitRoutingHeaderWithEnumTestCallable;
+  }
+
   @Override
   public UnaryCallable<Request, Empty> example1TestCallable() {
     throw new UnsupportedOperationException(

gapic-generator-java/src/test/proto/explicit_dynamic_routing_header_testing.proto

@@ -265,9 +265,37 @@ service ExplicitDynamicRoutingHeaderTesting {
       }
     };
   }
+
+  // This method echoes the request. This method exercises
+  // including a non-proto3-optional enum field in the URL path while sending the
+  // entire request object in the REST body.
+  rpc ImplicitRoutingHeaderWithEnumTest(EnumRequest) returns (EnumResponse) {
+    option (google.api.http) = {
+      post: "/v1beta1/{info.enum_test}"
+      body: "*"
+    };
+  }
+}
+
+message EnumRequest {
+  string name = 1;
+  EnumMessage info = 2;
 }
 
+message EnumResponse {
+  EnumRequest request = 1;
+}
 
+message EnumMessage {
+  enum EnumValues {
+    ENUM_VALUE_1 = 0;
+    ENUM_VALUE_2 = 1;
+    ENUM_VALUE_3 = 2;
+    ENUM_VALUE_4 = 3;
+  }
+  // scalar types
+  EnumValues enum_test = 22;
+}
 
 // Example message:
 //

showcase/gapic-showcase/src/main/java/com/google/showcase/v1beta1/stub/GrpcComplianceStub.java

@@ -273,7 +273,8 @@ protected GrpcComplianceStub(
                   builder.add("info.f_bool", String.valueOf(request.getInfo().getFBool()));
                   builder.add("info.f_double", String.valueOf(request.getInfo().getFDouble()));
                   builder.add("info.f_int32", String.valueOf(request.getInfo().getFInt32()));
-                  builder.add("info.f_kingdom", String.valueOf(request.getInfo().getFKingdom()));
+                  builder.add(
+                      "info.f_kingdom", String.valueOf(request.getInfo().getFKingdomValue()));
                   builder.add("info.f_string", String.valueOf(request.getInfo().getFString()));
                   return builder.build();
                 })

showcase/gapic-showcase/src/main/java/com/google/showcase/v1beta1/stub/HttpJsonComplianceStub.java

@@ -787,7 +787,8 @@ protected HttpJsonComplianceStub(
                   builder.add("info.f_bool", String.valueOf(request.getInfo().getFBool()));
                   builder.add("info.f_double", String.valueOf(request.getInfo().getFDouble()));
                   builder.add("info.f_int32", String.valueOf(request.getInfo().getFInt32()));
-                  builder.add("info.f_kingdom", String.valueOf(request.getInfo().getFKingdom()));
+                  builder.add(
+                      "info.f_kingdom", String.valueOf(request.getInfo().getFKingdomValue()));
                   builder.add("info.f_string", String.valueOf(request.getInfo().getFString()));
                   return builder.build();
                 })