3 files changed, 18 insertions, 10 deletions
diff --git a/src/zenstore/include/zenstore/cache/cachedisklayer.h b/src/zenstore/include/zenstore/cache/cachedisklayer.h
index b0b4f22cb..7de707a7f 100644
--- a/src/zenstore/include/zenstore/cache/cachedisklayer.h
+++ b/src/zenstore/include/zenstore/cache/cachedisklayer.h
@@ -178,10 +178,11 @@ public:
 	PutBatchHandle* BeginPutBatch(std::vector<bool>& OutResult);
 	void			EndPutBatch(PutBatchHandle* Batch) noexcept;
 
-	void Put(std::string_view	  Bucket,
+	bool Put(std::string_view	  Bucket,
 			 const IoHash&		  HashKey,
 			 const ZenCacheValue& Value,
 			 std::span<IoHash>	  References,
+			 bool				  Overwrite,
 			 PutBatchHandle*	  OptionalBatchHandle);
 	bool Drop();
 	bool DropBucket(std::string_view Bucket);
@@ -228,13 +229,17 @@ public:
 		void			Get(const IoHash& HashKey, GetBatchHandle& BatchHandle);
 
 		struct PutBatchHandle;
-		PutBatchHandle* BeginPutBatch(std::vector<bool>& OutResult);
-		void			EndPutBatch(PutBatchHandle* Batch) noexcept;
-		void	 Put(const IoHash& HashKey, const ZenCacheValue& Value, std::span<IoHash> References, PutBatchHandle* OptionalBatchHandle);
-		uint64_t MemCacheTrim(GcClock::TimePoint ExpireTime);
-		bool	 Drop();
-		void	 Flush();
-		void	 ScrubStorage(ScrubContext& Ctx);
+		PutBatchHandle*			BeginPutBatch(std::vector<bool>& OutResult);
+		void					EndPutBatch(PutBatchHandle* Batch) noexcept;
+		bool					Put(const IoHash&		 HashKey,
+									const ZenCacheValue& Value,
+									std::span<IoHash>	 References,
+									bool				 Overwrite,
+									PutBatchHandle*		 OptionalBatchHandle);
+		uint64_t				MemCacheTrim(GcClock::TimePoint ExpireTime);
+		bool					Drop();
+		void					Flush();
+		void					ScrubStorage(ScrubContext& Ctx);
 		RwLock::SharedLockScope GetGcReferencerLock();
 
 		struct ReferencesStats
diff --git a/src/zenstore/include/zenstore/cache/cacherpc.h b/src/zenstore/include/zenstore/cache/cacherpc.h
index da8cf69fe..d489a5386 100644
--- a/src/zenstore/include/zenstore/cache/cacherpc.h
+++ b/src/zenstore/include/zenstore/cache/cacherpc.h
@@ -60,6 +60,7 @@ enum class PutResult
 {
 	Success,
 	Fail,
+	Conflict,
 	Invalid,
 };
 
diff --git a/src/zenstore/include/zenstore/cache/structuredcachestore.h b/src/zenstore/include/zenstore/cache/structuredcachestore.h
index 82fec9b0e..1b5e0b76b 100644
--- a/src/zenstore/include/zenstore/cache/structuredcachestore.h
+++ b/src/zenstore/include/zenstore/cache/structuredcachestore.h
@@ -91,10 +91,11 @@ public:
 
 	bool Get(std::string_view Bucket, const IoHash& HashKey, ZenCacheValue& OutValue);
 	void Get(std::string_view Bucket, const IoHash& HashKey, GetBatchHandle& OptionalBatchHandle);
-	void Put(std::string_view	  Bucket,
+	bool Put(std::string_view	  Bucket,
 			 const IoHash&		  HashKey,
 			 const ZenCacheValue& Value,
 			 std::span<IoHash>	  References,
+			 bool				  Overwrite,
 			 PutBatchHandle*	  OptionalBatchHandle = nullptr);
 
 	bool DropBucket(std::string_view Bucket);
@@ -243,12 +244,13 @@ public:
 			 const IoHash&				HashKey,
 			 GetBatch&					BatchHandle);
 
-	void Put(const CacheRequestContext& Context,
+	bool Put(const CacheRequestContext& Context,
 			 std::string_view			Namespace,
 			 std::string_view			Bucket,
 			 const IoHash&				HashKey,
 			 const ZenCacheValue&		Value,
 			 std::span<IoHash>			References,
+			 bool						Overwrite,
 			 PutBatch*					OptionalBatchHandle = nullptr);
 
 	bool DropBucket(std::string_view Namespace, std::string_view Bucket);