Updated cache policy according to UE.

2 files changed, 61 insertions, 17 deletions

diff --git a/zenserver/cache/structuredcache.h b/zenserver/cache/structuredcache.h
index 3d9914606..51073d05d 100644
--- a/zenserver/cache/structuredcache.h
+++ b/zenserver/cache/structuredcache.h
@@ -20,7 +20,7 @@ class CasStore;
 class CidStore;
 class UpstreamCache;
 class ZenCacheStore;
-enum class CachePolicy : uint8_t;
+enum class CachePolicy : uint32_t;
 
 /**
  * Structured cache service. Imposes constraints on keys, supports blobs and
diff --git a/zenutil/include/zenutil/cache/cachepolicy.h b/zenutil/include/zenutil/cache/cachepolicy.h
index 0b5a70ea8..5cf19238e 100644
--- a/zenutil/include/zenutil/cache/cachepolicy.h
+++ b/zenutil/include/zenutil/cache/cachepolicy.h
@@ -13,24 +13,68 @@ namespace zen {
 class CbObjectView;
 class CbWriter;
 
-enum class CachePolicy : uint8_t
+enum class CachePolicy : uint32_t
 {
-	None			= 0,
-	QueryLocal		= 1 << 0,
-	QueryRemote		= 1 << 1,
-	Query			= QueryLocal | QueryRemote,
-	StoreLocal		= 1 << 2,
-	StoreRemote		= 1 << 3,
-	Store			= StoreLocal | StoreRemote,
-	SkipMeta		= 1 << 4,
-	SkipValue		= 1 << 5,
+	/** A value without any flags set. */
+	None = 0,
+
+	/** Allow a cache request to query local caches. */
+	QueryLocal = 1 << 0,
+	/** Allow a cache request to query remote caches. */
+	QueryRemote = 1 << 1,
+	/** Allow a cache request to query any caches. */
+	Query = QueryLocal | QueryRemote,
+
+	/** Allow cache records and values to be stored in local caches. */
+	StoreLocal = 1 << 2,
+	/** Allow cache records and values to be stored in remote caches. */
+	StoreRemote = 1 << 3,
+	/** Allow cache records and values to be stored in any caches. */
+	Store = StoreLocal | StoreRemote,
+
+	/** Skip fetching the metadata for record requests. */
+	SkipMeta = 1 << 4,
+	/** Skip fetching the value for record, chunk, or value requests. */
+	SkipValue = 1 << 5,
+	/** Skip fetching the attachments for record requests. */
 	SkipAttachments = 1 << 6,
-	SkipData		= SkipMeta | SkipValue | SkipAttachments,
-	SkipLocalCopy	= 1 << 7,
-	Local			= QueryLocal | StoreLocal,
-	Remote			= QueryRemote | StoreRemote,
-	Default			= Query | Store,
-	Disable			= None,
+	/**
+	 * Skip fetching the data for any requests.
+	 *
+	 * Put requests with skip flags may assume that record existence implies payload existence.
+	 */
+	SkipData = SkipMeta | SkipValue | SkipAttachments,
+
+	/**
+	 * Keep records in the cache for at least the duration of the session.
+	 *
+	 * This is a hint that the record may be accessed again in this session. This is mainly meant
+	 * to be used when subsequent accesses will not tolerate a cache miss.
+	 */
+	KeepAlive = 1 << 7,
+
+	/**
+	 * Partial output will be provided with the error status when a required payload is missing.
+	 *
+	 * This is meant for cases when the missing payloads can be individually recovered or rebuilt
+	 * without rebuilding the whole record. The cache automatically adds this flag when there are
+	 * other cache stores that it may be able to recover missing payloads from.
+	 *
+	 * Requests for records would return records where the missing payloads have a hash and size,
+	 * but no data. Requests for chunks or values would return the hash and size, but no data.
+	 */
+	PartialOnError = 1 << 8,
+
+	/** Allow cache requests to query and store records and values in local caches. */
+	Local = QueryLocal | StoreLocal,
+	/** Allow cache requests to query and store records and values in remote caches. */
+	Remote = QueryRemote | StoreRemote,
+
+	/** Allow cache requests to query and store records and values in any caches. */
+	Default = Query | Store,
+
+	/** Do not allow cache requests to query or store records and values in any caches. */
+	Disable = None,
 };
 
 gsl_DEFINE_ENUM_BITMASK_OPERATORS(CachePolicy);