Get rid of copy-pase of TChangeRecordContainer (#8352)

Author: CyberROFL

ydb/core/backup/impl/table_writer_impl.h

@@ -192,19 +192,9 @@ namespace NKikimr {
 
 template <>
 struct TChangeRecordContainer<NBackup::NImpl::TChangeRecord>
-    : public TBaseChangeRecordContainer
+    : public TBaseChangeRecordContainer<NBackup::NImpl::TChangeRecord>
 {
-    TChangeRecordContainer() = default;
-
-    explicit TChangeRecordContainer(TVector<NBackup::NImpl::TChangeRecord::TPtr>&& records)
-        : Records(std::move(records))
-    {}
-
-    TVector<NBackup::NImpl::TChangeRecord::TPtr> Records;
-
-    TString Out() override {
-        return TStringBuilder() << "[" << JoinSeq(",", Records) << "]";
-    }
+    using TBaseChangeRecordContainer<NBackup::NImpl::TChangeRecord>::TBaseChangeRecordContainer;
 };
 
 template <>

ydb/core/change_exchange/change_exchange.cpp

@@ -1,8 +1,5 @@
 #include "change_exchange.h"
 
-#include <util/string/builder.h>
-#include <util/string/join.h>
-
 namespace NKikimr::NChangeExchange {
 
 /// TEvEnqueueRecords
@@ -99,15 +96,14 @@ TEvChangeExchange::TEvRecords::TEvRecords(TChangeRecordVector&& records)
 {
 }
 
-
 TString TEvChangeExchange::TEvRecords::ToString() const {
-    return std::visit(
-        [&](auto& records){
-            return TStringBuilder() << ToStringHeader() << " {"
-                << " Records " << ((TBaseChangeRecordContainer*)records.get())->Out()
-            << " }";
-        },
-        Records);
+    auto visitor = [&](auto& records){
+        return TStringBuilder() << ToStringHeader() << " {"
+            << " Records " << reinterpret_cast<IChangeRecordContainer*>(records.get())->Out()
+        << " }";
+    };
+
+    return std::visit(visitor, Records);
 }
 
 /// TEvForgetRecords

ydb/core/change_exchange/change_exchange.h

@@ -7,6 +7,8 @@
 #include <ydb/core/scheme/scheme_pathid.h>
 
 #include <util/generic/vector.h>
+#include <util/string/builder.h>
+#include <util/string/join.h>
 
 namespace NKikimr {
 
@@ -22,12 +24,27 @@ namespace NBackup::NImpl {
     class TChangeRecord;
 }
 
-struct TBaseChangeRecordContainer {
-    virtual ~TBaseChangeRecordContainer() = default;
-    virtual TString Out() = 0;
+struct IChangeRecordContainer {
+    virtual ~IChangeRecordContainer() = default;
+    virtual TString Out() const = 0;
 };
 
-template <class T>
+template <typename T>
+struct TBaseChangeRecordContainer: public IChangeRecordContainer {
+    TVector<typename T::TPtr> Records;
+
+    TBaseChangeRecordContainer() = default;
+
+    explicit TBaseChangeRecordContainer(TVector<typename T::TPtr>&& records)
+        : Records(std::move(records))
+    {}
+
+    TString Out() const override {
+        return TStringBuilder() << "[" << JoinSeq(",", Records) << "]";
+    }
+};
+
+template <typename T>
 struct TChangeRecordContainer {};
 
 }

ydb/core/change_exchange/change_record.h

@@ -6,10 +6,10 @@
 
 namespace NKikimr {
 
-template <class TChangeRecord>
+template <typename TChangeRecord>
 struct TChangeRecordBuilderTrait;
 
-template <class TChangeRecord>
+template <typename TChangeRecord>
 struct TChangeRecordBuilderContextTrait {};
 
 } // namespace NKikimr
@@ -45,9 +45,11 @@ class IChangeRecord: public TThrRefBase {
 
     virtual TString ToString() const = 0;
     virtual void Out(IOutputStream& out) const = 0;
+
 }; // IChangeRecord
 
-template <typename T, typename TDerived> class TChangeRecordBuilder;
+template <typename T, typename TDerived>
+class TChangeRecordBuilder;
 
 class TChangeRecordBase: public IChangeRecord {
     template <typename T, typename TDerived> friend class TChangeRecordBuilder;

ydb/core/change_exchange/change_sender_common_ops.h

@@ -76,7 +76,7 @@ template <class TChangeRecord>
 class TBaseChangeSender {
     using TIncompleteRecord = TEvChangeExchange::TEvRequestRecords::TRecordInfo;
     // we need this to safely cast and call Out on a container
-    static_assert(std::derived_from<TChangeRecordContainer<TChangeRecord>, TBaseChangeRecordContainer>);
+    static_assert(std::derived_from<TChangeRecordContainer<TChangeRecord>, IChangeRecordContainer>);
 
     struct TEnqueuedRecord: TIncompleteRecord {
         bool ReEnqueued = false;

ydb/core/tx/datashard/change_record.h

@@ -129,19 +129,9 @@ namespace NKikimr {
 
 template <>
 struct TChangeRecordContainer<NDataShard::TChangeRecord>
-    : public TBaseChangeRecordContainer
+    : public TBaseChangeRecordContainer<NDataShard::TChangeRecord>
 {
-    TChangeRecordContainer() = default;
-
-    explicit TChangeRecordContainer(TVector<NDataShard::TChangeRecord::TPtr>&& records)
-        : Records(std::move(records))
-    {}
-
-    TVector<NDataShard::TChangeRecord::TPtr> Records;
-
-    TString Out() override {
-        return TStringBuilder() << "[" << JoinSeq(",", Records) << "]";
-    }
+    using TBaseChangeRecordContainer<NDataShard::TChangeRecord>::TBaseChangeRecordContainer;
 };
 
 }

ydb/core/tx/replication/service/json_change_record.cpp

@@ -107,11 +107,6 @@ void TChangeRecord::Serialize(NKikimrTxDataShard::TEvApplyReplicationChanges_TCh
     }
 }
 
-void TChangeRecord::Serialize(NKikimrTxDataShard::TEvApplyReplicationChanges_TChange& record) const {
-    TSerializationContext ctx;
-    Serialize(record, ctx);
-}
-
 TConstArrayRef<TCell> TChangeRecord::GetKey(TMemoryPool& pool) const {
     if (!Key) {
         TString error;

ydb/core/tx/replication/service/json_change_record.h

@@ -41,7 +41,6 @@ class TChangeRecord: public NChangeExchange::TChangeRecordBase {
     TString GetSourceId() const;
 
     void Serialize(NKikimrTxDataShard::TEvApplyReplicationChanges_TChange& record, TSerializationContext& ctx) const;
-    void Serialize(NKikimrTxDataShard::TEvApplyReplicationChanges_TChange& record) const;
 
     TConstArrayRef<TCell> GetKey(TMemoryPool& pool) const;
     TConstArrayRef<TCell> GetKey() const;
@@ -84,19 +83,9 @@ namespace NKikimr {
 
 template <>
 struct TChangeRecordContainer<NReplication::NService::TChangeRecord>
-    : public TBaseChangeRecordContainer
+    : public TBaseChangeRecordContainer<NReplication::NService::TChangeRecord>
 {
-    TChangeRecordContainer() = default;
-
-    explicit TChangeRecordContainer(TVector<NReplication::NService::TChangeRecord::TPtr>&& records)
-        : Records(std::move(records))
-    {}
-
-    TVector<NReplication::NService::TChangeRecord::TPtr> Records;
-
-    TString Out() override {
-        return TStringBuilder() << "[" << JoinSeq(",", Records) << "]";
-    }
+    using TBaseChangeRecordContainer<NReplication::NService::TChangeRecord>::TBaseChangeRecordContainer;
 };
 
 template <>