Report Incomplete Records To Client

When requesting partial records, report back when a record is incomplete via an "Incomplete" array of bools that is a sibling to the "Result" array for batch/rpc operations, or via the HttpResponseCode::PartialContent status code for individual record requests.

2 files changed, 44 insertions, 8 deletions

diff --git a/src/zenserver/cache/httpstructuredcache.cpp b/src/zenserver/cache/httpstructuredcache.cpp
index dc14465de..bc3f4ee20 100644
--- a/src/zenserver/cache/httpstructuredcache.cpp
+++ b/src/zenserver/cache/httpstructuredcache.cpp
@@ -821,7 +821,8 @@ HttpStructuredCacheService::HandleGetCacheRecord(HttpServerRequest& Request, con
 	const bool			 SkipData	   = EnumHasAllFlags(PolicyFromUrl, CachePolicy::SkipData);
 	const bool			 PartialRecord = EnumHasAllFlags(PolicyFromUrl, CachePolicy::PartialRecord);
 
-	bool		  Success = false;
+	bool		  Success	   = false;
+	uint32_t	  MissingCount = 0;
 	ZenCacheValue ClientResultValue;
 	if (!EnumHasAnyFlags(PolicyFromUrl, CachePolicy::Query))
 	{
@@ -844,7 +845,6 @@ HttpStructuredCacheService::HandleGetCacheRecord(HttpServerRequest& Request, con
 			if (ContentType == ZenContentType::kCbObject)
 			{
 				CbPackage		Package;
-				uint32_t		MissingCount  = 0;
 				CbValidateError ValidateError = CbValidateError::None;
 				if (CbObject PackageObject = ValidateAndReadCompactBinaryObject(std::move(ClientResultValue.Value), ValidateError);
 					ValidateError == CbValidateError::None)
@@ -936,7 +936,9 @@ HttpStructuredCacheService::HandleGetCacheRecord(HttpServerRequest& Request, con
 		else
 		{
 			// kCbPackage handled SkipData when constructing the ClientResultValue, kcbObject ignores SkipData
-			return Request.WriteResponse(HttpResponseCode::OK, ClientResultValue.Value.GetContentType(), ClientResultValue.Value);
+			return Request.WriteResponse((MissingCount == 0) ? HttpResponseCode::OK : HttpResponseCode::PartialContent,
+										 ClientResultValue.Value.GetContentType(),
+										 ClientResultValue.Value);
 		}
 	}
 	else if (!HasUpstream || !EnumHasAllFlags(PolicyFromUrl, CachePolicy::QueryRemote))
diff --git a/src/zenstore/cache/cacherpc.cpp b/src/zenstore/cache/cacherpc.cpp
index 77ca26409..fc34a28cf 100644
--- a/src/zenstore/cache/cacherpc.cpp
+++ b/src/zenstore/cache/cacherpc.cpp
@@ -860,14 +860,10 @@ CacheRpcHandler::HandleRpcGetCacheRecords(const CacheRequestContext& Context, Cb
 									  Key.Hash);
 						}
 					}
-					if (!Value.Exists && !EnumHasAllFlags(ValuePolicy, CachePolicy::SkipData))
+					if (!Value.Exists)
 					{
 						Request.Complete = false;
 					}
-					// Request.Complete does not need to be set to false for upstream SkipData attachments.
-					// In the PartialRecord==false case, the upstream will have failed the entire record if any SkipData attachment
-					// didn't exist and we will not get here. In the PartialRecord==true case, we do not need to inform the client of
-					// any missing SkipData attachments.
 				}
 				Request.ElapsedTimeUs += Timer.GetElapsedTimeUs();
 			}
@@ -883,7 +879,9 @@ CacheRpcHandler::HandleRpcGetCacheRecords(const CacheRequestContext& Context, Cb
 
 		ResponsePackage.ReserveAttachments(Requests.size());
 
+		eastl::fixed_vector<size_t, 4> IncompleteResultIndexes;
 		ResponseObject.BeginArray("Result"sv);
+		size_t ResultIndex = 0;
 		for (RecordRequestData& Request : Requests)
 		{
 			const CacheKey& Key = Request.Key;
@@ -899,6 +897,12 @@ CacheRpcHandler::HandleRpcGetCacheRecords(const CacheRequestContext& Context, Cb
 					}
 				}
 
+				if (!Request.Complete)
+				{
+					// If requesting a partial record, report back that the record overall is incomplete to the client
+					IncompleteResultIndexes.push_back(ResultIndex);
+				}
+
 				ZEN_DEBUG("GETCACHERECORD HIT - '{}/{}/{}' {}{} ({}) in {}",
 						  *Namespace,
 						  Key.Bucket,
@@ -935,8 +939,38 @@ CacheRpcHandler::HandleRpcGetCacheRecords(const CacheRequestContext& Context, Cb
 					m_CacheStats.MissCount++;
 				}
 			}
+			++ResultIndex;
 		}
 		ResponseObject.EndArray();
+
+		if (!IncompleteResultIndexes.empty())
+		{
+			size_t IndexIntoIncompleteResultArray = 0;
+			size_t IncompleteResultIndex		  = IncompleteResultIndexes[IndexIntoIncompleteResultArray];
+			ResultIndex							  = 0;
+			ResponseObject.BeginArray("Incomplete"sv);
+			for (ResultIndex = 0; ResultIndex < Requests.size(); ++ResultIndex)
+			{
+				if (IncompleteResultIndex == ResultIndex)
+				{
+					ResponseObject.AddBool(true);
+					if (++IndexIntoIncompleteResultArray >= IncompleteResultIndexes.size())
+					{
+						// Set IncompleteResultIndex into a value we can't encounter while marching ResultIndex forward
+						IncompleteResultIndex = 0;
+					}
+					else
+					{
+						IncompleteResultIndex = IncompleteResultIndexes[IndexIntoIncompleteResultArray];
+					}
+				}
+				else
+				{
+					ResponseObject.AddBool(true);
+				}
+			}
+			ResponseObject.EndArray();
+		}
 		ResponsePackage.SetObject(ResponseObject.Save());
 		return ResponsePackage;
 	}