rate limiter client refactoring: deduplicate structs representing HDRR settings (#14374)

Author: jepett0

include/ydb-cpp-sdk/client/rate_limiter/rate_limiter.h

@@ -3,6 +3,7 @@
 #include <ydb-cpp-sdk/client/driver/driver.h>
 
 namespace Ydb::RateLimiter {
+class CreateResourceRequest;
 class DescribeResourceResult;
 class HierarchicalDrrSettings;
 } // namespace Ydb::RateLimiter
@@ -11,9 +12,14 @@ namespace NYdb::inline V3::NRateLimiter {
 
 // Settings for hierarchical deficit round robin (HDRR) algorithm.
 template <class TDerived>
-struct THierarchicalDrrSettings : public TOperationRequestSettings<TDerived> {
+struct THierarchicalDrrSettings {
     using TSelf = TDerived;
 
+    THierarchicalDrrSettings() = default;
+    THierarchicalDrrSettings(const Ydb::RateLimiter::HierarchicalDrrSettings&);
+
+    void SerializeTo(Ydb::RateLimiter::HierarchicalDrrSettings&) const;
+
     // Resource consumption speed limit.
     // Value is required for root resource.
     // Must be nonnegative.
@@ -43,11 +49,19 @@ struct THierarchicalDrrSettings : public TOperationRequestSettings<TDerived> {
 };
 
 // Settings for create resource request.
-struct TCreateResourceSettings : public THierarchicalDrrSettings<TCreateResourceSettings> {
+struct TCreateResourceSettings
+    : public TOperationRequestSettings<TCreateResourceSettings>
+    , public THierarchicalDrrSettings<TCreateResourceSettings>
+{
+    TCreateResourceSettings() = default;
+    TCreateResourceSettings(const Ydb::RateLimiter::CreateResourceRequest&);
 };
 
 // Settings for alter resource request.
-struct TAlterResourceSettings : public THierarchicalDrrSettings<TAlterResourceSettings> {
+struct TAlterResourceSettings
+    : public TOperationRequestSettings<TAlterResourceSettings>
+    , public THierarchicalDrrSettings<TAlterResourceSettings>
+{
 };
 
 // Settings for drop resource request.
@@ -89,9 +103,10 @@ using TAsyncListResourcesResult = NThreading::TFuture<TListResourcesResult>;
 
 // Result for describe resource request.
 struct TDescribeResourceResult : public TStatus {
-    struct THierarchicalDrrProps {
+    // Note for YDB developers: THierarchicalDrrProps wrapper class exists for compatibility with older client code.
+    // Newer code should use the THierarchicalDrrSettings class directly.
+    struct THierarchicalDrrProps : public THierarchicalDrrSettings<THierarchicalDrrProps> {
         THierarchicalDrrProps(const Ydb::RateLimiter::HierarchicalDrrSettings&);
-        void SerializeTo(Ydb::RateLimiter::HierarchicalDrrSettings&) const;
 
         // Resource consumption speed limit.
         std::optional<double> GetMaxUnitsPerSecond() const {
@@ -113,12 +128,6 @@ struct TDescribeResourceResult : public TStatus {
         std::optional<double> GetPrefetchWatermark() const {
             return PrefetchWatermark_;
         }
-
-    private:
-        std::optional<double> MaxUnitsPerSecond_;
-        std::optional<double> MaxBurstSizeCoefficient_;
-        std::optional<double> PrefetchCoefficient_;
-        std::optional<double> PrefetchWatermark_;
     };
 
     TDescribeResourceResult(TStatus status, const Ydb::RateLimiter::DescribeResourceResult& result);

src/client/rate_limiter/rate_limiter.cpp

@@ -9,55 +9,71 @@
 
 namespace NYdb::inline V3::NRateLimiter {
 
-TListResourcesResult::TListResourcesResult(TStatus status, std::vector<std::string> paths)
-    : TStatus(std::move(status))
-    , ResourcePaths_(std::move(paths))
-{
-}
-
-TDescribeResourceResult::TDescribeResourceResult(TStatus status, const Ydb::RateLimiter::DescribeResourceResult& result)
-    : TStatus(std::move(status))
-    , ResourcePath_(result.resource().resource_path())
-    , HierarchicalDrrProps_(result.resource().hierarchical_drr())
-{
-}
-
-TDescribeResourceResult::THierarchicalDrrProps::THierarchicalDrrProps(const Ydb::RateLimiter::HierarchicalDrrSettings& settings) {
-    if (settings.max_units_per_second()) {
-        MaxUnitsPerSecond_ = settings.max_units_per_second();
+template <class TDerived>
+THierarchicalDrrSettings<TDerived>::THierarchicalDrrSettings(const Ydb::RateLimiter::HierarchicalDrrSettings& proto) {
+    if (proto.max_units_per_second()) {
+        MaxUnitsPerSecond_ = proto.max_units_per_second();
     }
 
-    if (settings.max_burst_size_coefficient()) {
-        MaxBurstSizeCoefficient_ = settings.max_burst_size_coefficient();
+    if (proto.max_burst_size_coefficient()) {
+        MaxBurstSizeCoefficient_ = proto.max_burst_size_coefficient();
     }
 
-    if (settings.prefetch_coefficient()) {
-        PrefetchCoefficient_ = settings.prefetch_coefficient();
+    if (proto.prefetch_coefficient()) {
+        PrefetchCoefficient_ = proto.prefetch_coefficient();
     }
 
-    if (settings.prefetch_watermark()) {
-        PrefetchWatermark_ = settings.prefetch_watermark();
+    if (proto.prefetch_watermark()) {
+        PrefetchWatermark_ = proto.prefetch_watermark();
     }
 }
 
-void TDescribeResourceResult::THierarchicalDrrProps::THierarchicalDrrProps::SerializeTo(Ydb::RateLimiter::HierarchicalDrrSettings& settings) const {
+template <class TDerived>
+void THierarchicalDrrSettings<TDerived>::SerializeTo(Ydb::RateLimiter::HierarchicalDrrSettings& proto) const {
     if (MaxUnitsPerSecond_) {
-        settings.set_max_units_per_second(*MaxUnitsPerSecond_);
+        proto.set_max_units_per_second(*MaxUnitsPerSecond_);
     }
 
     if (MaxBurstSizeCoefficient_) {
-        settings.set_max_burst_size_coefficient(*MaxBurstSizeCoefficient_);
+        proto.set_max_burst_size_coefficient(*MaxBurstSizeCoefficient_);
     }
 
     if (PrefetchCoefficient_) {
-        settings.set_prefetch_coefficient(*PrefetchCoefficient_);
+        proto.set_prefetch_coefficient(*PrefetchCoefficient_);
     }
 
     if (PrefetchWatermark_) {
-        settings.set_prefetch_watermark(*PrefetchWatermark_);
+        proto.set_prefetch_watermark(*PrefetchWatermark_);
     }
 }
 
+template struct THierarchicalDrrSettings<TCreateResourceSettings>;
+template struct THierarchicalDrrSettings<TAlterResourceSettings>;
+template struct THierarchicalDrrSettings<TDescribeResourceResult::THierarchicalDrrProps>;
+
+TCreateResourceSettings::TCreateResourceSettings(const Ydb::RateLimiter::CreateResourceRequest& proto)
+    : THierarchicalDrrSettings(proto.resource().hierarchical_drr())
+{
+}
+
+TListResourcesResult::TListResourcesResult(TStatus status, std::vector<std::string> paths)
+    : TStatus(std::move(status))
+    , ResourcePaths_(std::move(paths))
+{
+}
+
+TDescribeResourceResult::TDescribeResourceResult(TStatus status, const Ydb::RateLimiter::DescribeResourceResult& result)
+    : TStatus(std::move(status))
+    , ResourcePath_(result.resource().resource_path())
+    , HierarchicalDrrProps_(result.resource().hierarchical_drr())
+{
+}
+
+TDescribeResourceResult::THierarchicalDrrProps::THierarchicalDrrProps(const Ydb::RateLimiter::HierarchicalDrrSettings& settings)
+    : THierarchicalDrrSettings<THierarchicalDrrProps>(settings)
+{
+}
+
 class TRateLimiterClient::TImpl : public TClientImplCommon<TRateLimiterClient::TImpl> {
 public:
     TImpl(std::shared_ptr<TGRpcConnectionsImpl> connections, const TCommonClientSettings& settings)