Add "Accept" field in RPC request to gracefully handle requests from older instances (#180)

7 files changed, 160 insertions, 33 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index abe22c51b..73956912c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,6 @@
 ##
-- Feature: Add GC to projects store. Checks path to project file in UE side to determine when a project may be GCd on the Zen side.
+- Change: Responding with new wire format for RPC requests requires the requestor to add a `Accept` field in the request. This is to allow compatability with older clients for shared instances.
+- Feature: [Disabled] Add GC to projects store. Checks path to project file in UE side to determine when a project may be GCd on the Zen side.
 
 ## v0.1.7
 - Change: All RPC responses are now formatted using dedicated wire format, Zen server has fallback to enable compatability with legacy upstreams
diff --git a/zenserver-test/zenserver-test.cpp b/zenserver-test/zenserver-test.cpp
index 61c1e2df1..82b770e3c 100644
--- a/zenserver-test/zenserver-test.cpp
+++ b/zenserver-test/zenserver-test.cpp
@@ -1340,7 +1340,7 @@ TEST_CASE("zcache.rpc")
 			((uint32_t*)(KeyHash.Hash))[0] = Key;
 			const zen::CacheKey CacheKey   = zen::CacheKey::Create(Bucket, KeyHash);
 
-			cacherequests::PutCacheRecordsRequest Request = {.Namespace = std::string(Namespace)};
+			cacherequests::PutCacheRecordsRequest Request = {.AcceptMagic = kCbPkgMagic, .Namespace = std::string(Namespace)};
 			AppendCacheRecord(Request, CacheKey, PayloadSize, CachePolicy::Default);
 			OutKeys.push_back(CacheKey);
 
@@ -1369,7 +1369,9 @@ TEST_CASE("zcache.rpc")
 							  std::string_view		   Namespace,
 							  std::span<zen::CacheKey> Keys,
 							  zen::CachePolicy		   Policy) -> GetCacheRecordResult {
-		cacherequests::GetCacheRecordsRequest Request = {.DefaultPolicy = Policy, .Namespace = std::string(Namespace)};
+		cacherequests::GetCacheRecordsRequest Request = {.AcceptMagic	= kCbPkgMagic,
+														 .DefaultPolicy = Policy,
+														 .Namespace		= std::string(Namespace)};
 		for (const CacheKey& Key : Keys)
 		{
 			Request.Requests.push_back({.Key = Key});
@@ -1592,7 +1594,7 @@ TEST_CASE("zcache.failing.upstream")
 												size_t			 PayloadSize = 8192) -> std::vector<CacheKey> {
 		std::vector<zen::CacheKey> OutKeys;
 
-		cacherequests::PutCacheRecordsRequest Request = {.Namespace = std::string(Namespace)};
+		cacherequests::PutCacheRecordsRequest Request = {.AcceptMagic = kCbPkgMagic, .Namespace = std::string(Namespace)};
 		for (size_t Key = 1; Key <= Num; ++Key)
 		{
 			zen::IoHash KeyHash;
@@ -1631,7 +1633,9 @@ TEST_CASE("zcache.failing.upstream")
 							  std::string_view		   Namespace,
 							  std::span<zen::CacheKey> Keys,
 							  zen::CachePolicy		   Policy) -> GetCacheRecordResult {
-		cacherequests::GetCacheRecordsRequest Request = {.DefaultPolicy = Policy, .Namespace = std::string(Namespace)};
+		cacherequests::GetCacheRecordsRequest Request = {.AcceptMagic	= kCbPkgMagic,
+														 .DefaultPolicy = Policy,
+														 .Namespace		= std::string(Namespace)};
 		for (const CacheKey& Key : Keys)
 		{
 			Request.Requests.push_back({.Key = Key});
@@ -2008,7 +2012,9 @@ TEST_CASE("zcache.rpc.allpolicies")
 	// PutCacheRecords
 	{
 		CachePolicy							  BatchDefaultPolicy = CachePolicy::Default;
-		cacherequests::PutCacheRecordsRequest Request = {.DefaultPolicy = BatchDefaultPolicy, .Namespace = std::string(TestNamespace)};
+		cacherequests::PutCacheRecordsRequest Request			 = {.AcceptMagic   = kCbPkgMagic,
+																	.DefaultPolicy = BatchDefaultPolicy,
+																	.Namespace	   = std::string(TestNamespace)};
 		Request.Requests.reserve(PutRequests.size());
 		for (CachePutRequest& PutRequest : PutRequests)
 		{
@@ -2036,7 +2042,9 @@ TEST_CASE("zcache.rpc.allpolicies")
 	{
 		CachePolicy BatchDefaultPolicy = CachePolicy::Default;
 
-		cacherequests::PutCacheValuesRequest Request = {.DefaultPolicy = BatchDefaultPolicy, .Namespace = std::string(TestNamespace)};
+		cacherequests::PutCacheValuesRequest Request = {.AcceptMagic   = kCbPkgMagic,
+														.DefaultPolicy = BatchDefaultPolicy,
+														.Namespace	   = std::string(TestNamespace)};
 		Request.Requests.reserve(PutValueRequests.size());
 		for (CachePutValueRequest& PutRequest : PutValueRequests)
 		{
@@ -2073,7 +2081,9 @@ TEST_CASE("zcache.rpc.allpolicies")
 	// GetCacheRecords
 	{
 		CachePolicy							  BatchDefaultPolicy = CachePolicy::Default;
-		cacherequests::GetCacheRecordsRequest Request = {.DefaultPolicy = BatchDefaultPolicy, .Namespace = std::string(TestNamespace)};
+		cacherequests::GetCacheRecordsRequest Request			 = {.AcceptMagic   = kCbPkgMagic,
+																	.DefaultPolicy = BatchDefaultPolicy,
+																	.Namespace	   = std::string(TestNamespace)};
 		Request.Requests.reserve(GetRequests.size());
 		for (CacheGetRequest& GetRequest : GetRequests)
 		{
@@ -2150,7 +2160,8 @@ TEST_CASE("zcache.rpc.allpolicies")
 	{
 		CachePolicy BatchDefaultPolicy = CachePolicy::Default;
 
-		cacherequests::GetCacheValuesRequest GetCacheValuesRequest = {.DefaultPolicy = BatchDefaultPolicy,
+		cacherequests::GetCacheValuesRequest GetCacheValuesRequest = {.AcceptMagic	 = kCbPkgMagic,
+																	  .DefaultPolicy = BatchDefaultPolicy,
 																	  .Namespace	 = std::string(TestNamespace)};
 		GetCacheValuesRequest.Requests.reserve(GetValueRequests.size());
 		for (CacheGetValueRequest& GetRequest : GetValueRequests)
@@ -2215,7 +2226,8 @@ TEST_CASE("zcache.rpc.allpolicies")
 			return A.Key.Hash < B.Key.Hash;
 		});
 		CachePolicy							 BatchDefaultPolicy	   = CachePolicy::Default;
-		cacherequests::GetCacheChunksRequest GetCacheChunksRequest = {.DefaultPolicy = BatchDefaultPolicy,
+		cacherequests::GetCacheChunksRequest GetCacheChunksRequest = {.AcceptMagic	 = kCbPkgMagic,
+																	  .DefaultPolicy = BatchDefaultPolicy,
 																	  .Namespace	 = std::string(TestNamespace)};
 		GetCacheChunksRequest.Requests.reserve(ChunkRequests.size());
 		for (CacheGetChunkRequest& ChunkRequest : ChunkRequests)
diff --git a/zenserver/cache/structuredcache.cpp b/zenserver/cache/structuredcache.cpp
index 75fb8ac41..0e2462a4a 100644
--- a/zenserver/cache/structuredcache.cpp
+++ b/zenserver/cache/structuredcache.cpp
@@ -1159,12 +1159,13 @@ HttpStructuredCacheService::HandleRpcPutCacheRecords(zen::HttpServerRequest& Req
 {
 	ZEN_TRACE_CPU("Z$::RpcPutCacheRecords");
 	CbObjectView BatchObject = BatchRequest.GetObject();
+	ZEN_ASSERT(BatchObject["Method"sv].AsString() == "PutCacheRecords"sv);
+
+	uint32_t AcceptMagic = BatchObject["Accept"sv].AsUInt32();
 
 	CbObjectView Params = BatchObject["Params"sv].AsObjectView();
 	CachePolicy	 DefaultPolicy;
 
-	ZEN_ASSERT(BatchObject["Method"sv].AsString() == "PutCacheRecords"sv);
-
 	std::string_view		   PolicyText = Params["DefaultPolicy"].AsString();
 	std::optional<std::string> Namespace  = GetRpcRequestNamespace(Params);
 	if (!Namespace)
@@ -1211,9 +1212,20 @@ HttpStructuredCacheService::HandleRpcPutCacheRecords(zen::HttpServerRequest& Req
 	CbPackage RpcResponse;
 	RpcResponse.SetObject(ResponseObject.Save());
 
-	CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResponse);
+	if (AcceptMagic == kCbPkgMagic)
+	{
+		CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResponse);
+		Request.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+	}
+	else
+	{
+		BinaryWriter MemStream;
+		RpcResponse.Save(MemStream);
 
-	Request.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+		Request.WriteResponse(HttpResponseCode::OK,
+							  HttpContentType::kCbPackage,
+							  IoBuffer(IoBuffer::Wrap, MemStream.GetData(), MemStream.GetSize()));
+	}
 }
 
 HttpStructuredCacheService::PutResult
@@ -1302,9 +1314,12 @@ HttpStructuredCacheService::HandleRpcGetCacheRecords(zen::HttpServerRequest& Htt
 {
 	ZEN_TRACE_CPU("Z$::RpcGetCacheRecords");
 
-	CbObjectView Params = RpcRequest["Params"sv].AsObjectView();
 	ZEN_ASSERT(RpcRequest["Method"sv].AsString() == "GetCacheRecords"sv);
 
+	uint32_t AcceptMagic = RpcRequest["Accept"sv].AsUInt32();
+
+	CbObjectView Params = RpcRequest["Params"sv].AsObjectView();
+
 	struct ValueRequestData
 	{
 		Oid				 ValueId;
@@ -1632,9 +1647,20 @@ HttpStructuredCacheService::HandleRpcGetCacheRecords(zen::HttpServerRequest& Htt
 	ResponseObject.EndArray();
 	ResponsePackage.SetObject(ResponseObject.Save());
 
-	CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(ResponsePackage);
+	if (AcceptMagic == kCbPkgMagic)
+	{
+		CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(ResponsePackage);
+		HttpRequest.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+	}
+	else
+	{
+		BinaryWriter MemStream;
+		ResponsePackage.Save(MemStream);
 
-	HttpRequest.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+		HttpRequest.WriteResponse(HttpResponseCode::OK,
+								  HttpContentType::kCbPackage,
+								  IoBuffer(IoBuffer::Wrap, MemStream.GetData(), MemStream.GetSize()));
+	}
 }
 
 void
@@ -1642,10 +1668,11 @@ HttpStructuredCacheService::HandleRpcPutCacheValues(zen::HttpServerRequest& Requ
 {
 	ZEN_TRACE_CPU("Z$::RpcPutCacheValues");
 	CbObjectView BatchObject = BatchRequest.GetObject();
+	ZEN_ASSERT(BatchObject["Method"sv].AsString() == "PutCacheValues"sv);
 
-	CbObjectView Params = BatchObject["Params"sv].AsObjectView();
+	uint32_t AcceptMagic = BatchObject["Accept"sv].AsUInt32();
 
-	ZEN_ASSERT(BatchObject["Method"sv].AsString() == "PutCacheValues"sv);
+	CbObjectView Params = BatchObject["Params"sv].AsObjectView();
 
 	std::string_view		   PolicyText	 = Params["DefaultPolicy"].AsString();
 	CachePolicy				   DefaultPolicy = !PolicyText.empty() ? ParseCachePolicy(PolicyText) : CachePolicy::Default;
@@ -1742,9 +1769,20 @@ HttpStructuredCacheService::HandleRpcPutCacheValues(zen::HttpServerRequest& Requ
 	CbPackage RpcResponse;
 	RpcResponse.SetObject(ResponseObject.Save());
 
-	CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResponse);
+	if (AcceptMagic == kCbPkgMagic)
+	{
+		CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResponse);
+		Request.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+	}
+	else
+	{
+		BinaryWriter MemStream;
+		RpcResponse.Save(MemStream);
 
-	Request.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+		Request.WriteResponse(HttpResponseCode::OK,
+							  HttpContentType::kCbPackage,
+							  IoBuffer(IoBuffer::Wrap, MemStream.GetData(), MemStream.GetSize()));
+	}
 }
 
 void
@@ -1752,6 +1790,10 @@ HttpStructuredCacheService::HandleRpcGetCacheValues(zen::HttpServerRequest& Http
 {
 	ZEN_TRACE_CPU("Z$::RpcGetCacheValues");
 
+	ZEN_ASSERT(RpcRequest["Method"sv].AsString() == "GetCacheValues"sv);
+
+	uint32_t AcceptMagic = RpcRequest["Accept"sv].AsUInt32();
+
 	CbObjectView			   Params		 = RpcRequest["Params"sv].AsObjectView();
 	std::string_view		   PolicyText	 = Params["DefaultPolicy"sv].AsString();
 	CachePolicy				   DefaultPolicy = !PolicyText.empty() ? ParseCachePolicy(PolicyText) : CachePolicy::Default;
@@ -1771,8 +1813,6 @@ HttpStructuredCacheService::HandleRpcGetCacheValues(zen::HttpServerRequest& Http
 	};
 	std::vector<RequestData> Requests;
 
-	ZEN_ASSERT(RpcRequest["Method"sv].AsString() == "GetCacheValues"sv);
-
 	std::vector<size_t> RemoteRequestIndexes;
 
 	for (CbFieldView RequestField : Params["Requests"sv])
@@ -1934,9 +1974,21 @@ HttpStructuredCacheService::HandleRpcGetCacheValues(zen::HttpServerRequest& Http
 	ResponseObject.EndArray();
 
 	RpcResponse.SetObject(ResponseObject.Save());
-	CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResponse);
 
-	HttpRequest.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+	if (AcceptMagic == kCbPkgMagic)
+	{
+		CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResponse);
+		HttpRequest.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+	}
+	else
+	{
+		BinaryWriter MemStream;
+		RpcResponse.Save(MemStream);
+
+		HttpRequest.WriteResponse(HttpResponseCode::OK,
+								  HttpContentType::kCbPackage,
+								  IoBuffer(IoBuffer::Wrap, MemStream.GetData(), MemStream.GetSize()));
+	}
 }
 
 namespace cache::detail {
@@ -1990,9 +2042,18 @@ HttpStructuredCacheService::HandleRpcGetCacheChunks(zen::HttpServerRequest& Http
 	std::vector<ChunkRequest*>		RecordRequests;	 // The ChunkRequests that are requesting a subvalue from a Record Key
 	std::vector<ChunkRequest*>		ValueRequests;	 // The ChunkRequests that are requesting a Value Key
 	std::vector<CacheChunkRequest*> UpstreamChunks;	 // ChunkRequests that we need to send to the upstream
+	uint32_t						AcceptMagic = 0;
 
 	// Parse requests from the CompactBinary body of the RpcRequest and divide it into RecordRequests and ValueRequests
-	if (!ParseGetCacheChunksRequest(Namespace, RecordKeys, Records, RequestKeys, Requests, RecordRequests, ValueRequests, RpcRequest))
+	if (!ParseGetCacheChunksRequest(AcceptMagic,
+									Namespace,
+									RecordKeys,
+									Records,
+									RequestKeys,
+									Requests,
+									RecordRequests,
+									ValueRequests,
+									RpcRequest))
 	{
 		return HttpRequest.WriteResponse(HttpResponseCode::BadRequest);
 	}
@@ -2008,11 +2069,12 @@ HttpStructuredCacheService::HandleRpcGetCacheChunks(zen::HttpServerRequest& Http
 	GetUpstreamCacheChunks(Namespace, UpstreamChunks, RequestKeys, Requests);
 
 	// Send the payload and descriptive data about each chunk to the client
-	WriteGetCacheChunksResponse(Namespace, Requests, HttpRequest);
+	WriteGetCacheChunksResponse(AcceptMagic, Namespace, Requests, HttpRequest);
 }
 
 bool
-HttpStructuredCacheService::ParseGetCacheChunksRequest(std::string&								  Namespace,
+HttpStructuredCacheService::ParseGetCacheChunksRequest(uint32_t&								  AcceptMagic,
+													   std::string&								  Namespace,
 													   std::vector<CacheKeyRequest>&			  RecordKeys,
 													   std::vector<cache::detail::RecordBody>&	  Records,
 													   std::vector<CacheChunkRequest>&			  RequestKeys,
@@ -2025,6 +2087,8 @@ HttpStructuredCacheService::ParseGetCacheChunksRequest(std::string&								  Nam
 
 	ZEN_ASSERT(RpcRequest["Method"sv].AsString() == "GetCacheChunks"sv);
 
+	AcceptMagic = RpcRequest["Accept"sv].AsUInt32();
+
 	CbObjectView	 Params			   = RpcRequest["Params"sv].AsObjectView();
 	std::string_view DefaultPolicyText = Params["DefaultPolicy"sv].AsString();
 	CachePolicy		 DefaultPolicy	   = !DefaultPolicyText.empty() ? ParseCachePolicy(DefaultPolicyText) : CachePolicy::Default;
@@ -2375,7 +2439,8 @@ HttpStructuredCacheService::GetUpstreamCacheChunks(std::string_view							 Names
 }
 
 void
-HttpStructuredCacheService::WriteGetCacheChunksResponse(std::string_view						  Namespace,
+HttpStructuredCacheService::WriteGetCacheChunksResponse(uint32_t								  AcceptMagic,
+														std::string_view						  Namespace,
 														std::vector<cache::detail::ChunkRequest>& Requests,
 														zen::HttpServerRequest&					  HttpRequest)
 {
@@ -2438,9 +2503,20 @@ HttpStructuredCacheService::WriteGetCacheChunksResponse(std::string_view
 
 	RpcResponse.SetObject(Writer.Save());
 
-	CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResponse);
+	if (AcceptMagic == kCbPkgMagic)
+	{
+		CompositeBuffer RpcResponseBuffer = FormatPackageMessageBuffer(RpcResponse);
+		HttpRequest.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+	}
+	else
+	{
+		BinaryWriter MemStream;
+		RpcResponse.Save(MemStream);
 
-	HttpRequest.WriteResponse(HttpResponseCode::OK, HttpContentType::kCbPackage, RpcResponseBuffer);
+		HttpRequest.WriteResponse(HttpResponseCode::OK,
+								  HttpContentType::kCbPackage,
+								  IoBuffer(IoBuffer::Wrap, MemStream.GetData(), MemStream.GetSize()));
+	}
 }
 
 void
diff --git a/zenserver/cache/structuredcache.h b/zenserver/cache/structuredcache.h
index 8eca17edc..bda838dbc 100644
--- a/zenserver/cache/structuredcache.h
+++ b/zenserver/cache/structuredcache.h
@@ -117,7 +117,8 @@ private:
 	PutResult	 PutCacheRecord(PutRequestData& Request, const CbPackage* Package);
 
 	/** HandleRpcGetCacheChunks Helper: Parse the Body object into RecordValue Requests and Value Requests. */
-	bool ParseGetCacheChunksRequest(std::string&							   Namespace,
+	bool ParseGetCacheChunksRequest(uint32_t&								   AcceptMagic,
+									std::string&							   Namespace,
 									std::vector<CacheKeyRequest>&			   RecordKeys,
 									std::vector<cache::detail::RecordBody>&	   Records,
 									std::vector<CacheChunkRequest>&			   RequestKeys,
@@ -141,7 +142,8 @@ private:
 								std::vector<CacheChunkRequest>&			  RequestKeys,
 								std::vector<cache::detail::ChunkRequest>& Requests);
 	/** HandleRpcGetCacheChunks Helper: Send response message containing all chunk results. */
-	void WriteGetCacheChunksResponse(std::string_view						   Namespace,
+	void WriteGetCacheChunksResponse(uint32_t								   AcceptMagic,
+									 std::string_view						   Namespace,
 									 std::vector<cache::detail::ChunkRequest>& Requests,
 									 zen::HttpServerRequest&				   HttpRequest);
 
diff --git a/zenserver/upstream/upstreamcache.cpp b/zenserver/upstream/upstreamcache.cpp
index ac75285c7..f9673bcd6 100644
--- a/zenserver/upstream/upstreamcache.cpp
+++ b/zenserver/upstream/upstreamcache.cpp
@@ -860,6 +860,7 @@ namespace detail {
 			CbObjectWriter BatchRequest;
 			BatchRequest << "Method"sv
 						 << "GetCacheRecords"sv;
+			BatchRequest << "Accept"sv << kCbPkgMagic;
 
 			BatchRequest.BeginObject("Params"sv);
 			{
@@ -982,6 +983,7 @@ namespace detail {
 			CbObjectWriter BatchRequest;
 			BatchRequest << "Method"sv
 						 << "GetCacheValues"sv;
+			BatchRequest << "Accept"sv << kCbPkgMagic;
 
 			BatchRequest.BeginObject("Params"sv);
 			{
@@ -1101,6 +1103,7 @@ namespace detail {
 			CbObjectWriter BatchRequest;
 			BatchRequest << "Method"sv
 						 << "GetCacheChunks"sv;
+			BatchRequest << "Accept"sv << kCbPkgMagic;
 
 			BatchRequest.BeginObject("Params"sv);
 			{
@@ -1289,6 +1292,7 @@ namespace detail {
 					CbObjectWriter BatchWriter;
 					BatchWriter << "Method"sv
 								<< "PutCacheValues"sv;
+					BatchWriter << "Accept"sv << kCbPkgMagic;
 
 					BatchWriter.BeginObject("Params"sv);
 					{
diff --git a/zenutil/cache/cacherequests.cpp b/zenutil/cache/cacherequests.cpp
index 2c14ef35b..0ac6c35ed 100644
--- a/zenutil/cache/cacherequests.cpp
+++ b/zenutil/cache/cacherequests.cpp
@@ -175,6 +175,7 @@ namespace cacherequests {
 	{
 		CbObjectView BatchObject = Package.GetObject();
 		ZEN_ASSERT(BatchObject["Method"].AsString() == "PutCacheRecords");
+		AcceptMagic = BatchObject["AcceptType"].AsUInt32(0);
 
 		CbObjectView			   Params			= BatchObject["Params"].AsObjectView();
 		std::optional<std::string> RequestNamespace = GetRequestNamespace(Params);
@@ -240,6 +241,11 @@ namespace cacherequests {
 		CbObjectWriter Writer;
 		Writer << "Method"
 			   << "PutCacheRecords";
+		if (AcceptMagic != 0)
+		{
+			Writer << "Accept" << AcceptMagic;
+		}
+
 		Writer.BeginObject("Params");
 		{
 			Writer << "DefaultPolicy" << WriteToString<128>(DefaultPolicy);
@@ -325,6 +331,7 @@ namespace cacherequests {
 	bool GetCacheRecordsRequest::Parse(const CbObjectView& RpcRequest)
 	{
 		ZEN_ASSERT(RpcRequest["Method"].AsString() == "GetCacheRecords");
+		AcceptMagic = RpcRequest["AcceptType"].AsUInt32(0);
 
 		CbObjectView			   Params			= RpcRequest["Params"].AsObjectView();
 		std::optional<std::string> RequestNamespace = GetRequestNamespace(Params);
@@ -361,6 +368,11 @@ namespace cacherequests {
 	{
 		Writer << "Method"
 			   << "GetCacheRecords";
+		if (AcceptMagic != 0)
+		{
+			Writer << "Accept" << AcceptMagic;
+		}
+
 		Writer.BeginObject("Params");
 		{
 			Writer << "DefaultPolicy" << WriteToString<128>(DefaultPolicy);
@@ -513,6 +525,7 @@ namespace cacherequests {
 	{
 		CbObjectView BatchObject = Package.GetObject();
 		ZEN_ASSERT(BatchObject["Method"].AsString() == "PutCacheValues");
+		AcceptMagic = BatchObject["AcceptType"].AsUInt32(0);
 
 		CbObjectView			   Params			= BatchObject["Params"].AsObjectView();
 		std::optional<std::string> RequestNamespace = cacherequests::GetRequestNamespace(Params);
@@ -558,6 +571,10 @@ namespace cacherequests {
 		CbObjectWriter Writer;
 		Writer << "Method"
 			   << "PutCacheValues";
+		if (AcceptMagic != 0)
+		{
+			Writer << "Accept" << AcceptMagic;
+		}
 
 		Writer.BeginObject("Params");
 		{
@@ -637,6 +654,7 @@ namespace cacherequests {
 	bool GetCacheValuesRequest::Parse(const CbObjectView& BatchObject)
 	{
 		ZEN_ASSERT(BatchObject["Method"].AsString() == "GetCacheValues");
+		AcceptMagic = BatchObject["AcceptType"].AsUInt32(0);
 
 		CbObjectView			   Params			= BatchObject["Params"].AsObjectView();
 		std::optional<std::string> RequestNamespace = cacherequests::GetRequestNamespace(Params);
@@ -672,6 +690,10 @@ namespace cacherequests {
 		CbObjectWriter Writer;
 		Writer << "Method"
 			   << "GetCacheValues";
+		if (AcceptMagic != 0)
+		{
+			Writer << "Accept" << AcceptMagic;
+		}
 
 		Writer.BeginObject("Params");
 		{
@@ -793,6 +815,7 @@ namespace cacherequests {
 	bool GetCacheChunksRequest::Parse(const CbObjectView& BatchObject)
 	{
 		ZEN_ASSERT(BatchObject["Method"].AsString() == "GetCacheChunks");
+		AcceptMagic = BatchObject["AcceptType"].AsUInt32(0);
 
 		CbObjectView			   Params			= BatchObject["Params"].AsObjectView();
 		std::optional<std::string> RequestNamespace = cacherequests::GetRequestNamespace(Params);
@@ -833,6 +856,10 @@ namespace cacherequests {
 		CbObjectWriter Writer;
 		Writer << "Method"
 			   << "GetCacheChunks";
+		if (AcceptMagic != 0)
+		{
+			Writer << "Accept" << AcceptMagic;
+		}
 
 		Writer.BeginObject("Params");
 		{
diff --git a/zenutil/include/zenutil/cache/cacherequests.h b/zenutil/include/zenutil/cache/cacherequests.h
index ffb0f8d5f..4eebd3121 100644
--- a/zenutil/include/zenutil/cache/cacherequests.h
+++ b/zenutil/include/zenutil/cache/cacherequests.h
@@ -74,6 +74,7 @@ namespace cacherequests {
 
 	struct PutCacheRecordsRequest
 	{
+		uint32_t						   AcceptMagic	 = 0;
 		CachePolicy						   DefaultPolicy = CachePolicy::Default;
 		std::string						   Namespace;
 		std::vector<PutCacheRecordRequest> Requests;
@@ -105,6 +106,7 @@ namespace cacherequests {
 
 	struct GetCacheRecordsRequest
 	{
+		uint32_t						   AcceptMagic	 = 0;
 		CachePolicy						   DefaultPolicy = CachePolicy::Default;
 		std::string						   Namespace;
 		std::vector<GetCacheRecordRequest> Requests;
@@ -150,6 +152,7 @@ namespace cacherequests {
 
 	struct PutCacheValuesRequest
 	{
+		uint32_t						  AcceptMagic	= 0;
 		CachePolicy						  DefaultPolicy = CachePolicy::Default;
 		std::string						  Namespace;
 		std::vector<PutCacheValueRequest> Requests;
@@ -177,6 +180,7 @@ namespace cacherequests {
 
 	struct GetCacheValuesRequest
 	{
+		uint32_t						  AcceptMagic	= 0;
 		CachePolicy						  DefaultPolicy = CachePolicy::Default;
 		std::string						  Namespace;
 		std::vector<GetCacheValueRequest> Requests;
@@ -217,6 +221,7 @@ namespace cacherequests {
 
 	struct GetCacheChunksRequest
 	{
+		uint32_t						  AcceptMagic	= 0;
 		CachePolicy						  DefaultPolicy = CachePolicy::Default;
 		std::string						  Namespace;
 		std::vector<GetCacheChunkRequest> Requests;