@VisibleForTesting
    ServiceSpecification generate(List<ServiceInfo> services,
                                  DescriptiveTypeInfoProvider descriptiveTypeInfoProvider) {
        return ServiceSpecification.generate(
                services, typeSignature -> newDescriptiveTypeInfo(typeSignature, descriptiveTypeInfoProvider));
    }
{@link DocServicePlugin} implementation that supports {@link GrpcService}s.
grpc/src/main/java/com/linecorp/armeria/internal/server/grpc/GrpcDocServicePlugin.java