disable partial getcachechunk responses (#19)

2 files changed, 7 insertions, 2 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5bd4fc89d..f96b026ec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,7 +8,6 @@
 - Bugfix: Use TemporaryFile and MoveTemporaryIntoPlace to avoid leaving partial files on error
 - Bugfix: Install Ctrl+C handler earlier when doing `zen oplog-export` and `zen oplog-export` to properly cancel jobs
 - Feature: Added option `--access-token-path` to `zen oplog-export` and `zen-oplog-import` enabling it to read a cloud access token from a json file
-- Feature: Structured cache RPC call GetCacheChunks can now respond with partial chunks. Requires the accept flag kAllowPartialCacheChunks to be set in the request
 - Improvement: Add ability to block a set of CAS entries from GC in project store
 - Improvement: Httpasio explicitly close acceptor sockets
 - Improvement: Httpasio add retry for desired port
diff --git a/src/zenstore/cache/cacherpc.cpp b/src/zenstore/cache/cacherpc.cpp
index 27bc4b016..84ca5c5e3 100644
--- a/src/zenstore/cache/cacherpc.cpp
+++ b/src/zenstore/cache/cacherpc.cpp
@@ -1549,7 +1549,13 @@ CacheRpcHandler::WriteGetCacheChunksResponse([[maybe_unused]] const CacheRequest
 
 	using namespace cache::detail;
 
-	const bool AcceptsPartialChunks = EnumHasAnyFlags(AcceptOptions, RpcAcceptOptions::kAllowPartialCacheChunks);
+	const bool AcceptsPartialChunks = EnumHasAnyFlags(AcceptOptions, RpcAcceptOptions::kAllowPartialCacheChunks) && false;
+	// TODO: We need to redesign how we respond with partial chunks as we can get requests for multiple parts of the same chunk
+	// and we currently identify chunks by the full chunks RawHash making it impossible to distinguish between sections for partial chunks.
+	// Also, UE currently does the lookup by checking the RawHash *inside* the attachment which will break as sections of compressed
+	// buffers has a RawHash of zero (as we don't want to re-hash the section)
+	// zen side handles this as it separates the lookup hash from the hash inside the attachment, but it still can't tell two partial
+	// section from the same chunk apart.
 
 	CbPackage	   RpcResponse;
 	CbObjectWriter Writer;