don't throw exception if sidecar file is missing (#126)

* Don't throw exception if sidecar file is missing.
* Log reasons for rejecting sidecar file

1 files changed, 14 insertions, 1 deletions

diff --git a/src/zenstore/cache/cachedisklayer.cpp b/src/zenstore/cache/cachedisklayer.cpp
index 94636bb59..c80fc59d8 100644
--- a/src/zenstore/cache/cachedisklayer.cpp
+++ b/src/zenstore/cache/cachedisklayer.cpp
@@ -516,7 +516,8 @@ BucketManifestSerializer::ReadSidecarFile(RwLock::ExclusiveLockScope&								  B
 
 	if (Ec)
 	{
-		throw std::system_error(Ec, fmt::format("failed to open sidecar file '{}'", SidecarPath));
+		ZEN_WARN("Failed to read sidecar file '{}'. Reason: '{}'", SidecarPath, Ec.message());
+		return false;
 	}
 
 	uint64_t FileSize = SidecarFile.FileSize();
@@ -525,6 +526,10 @@ BucketManifestSerializer::ReadSidecarFile(RwLock::ExclusiveLockScope&								  B
 
 	if (FileSize < sizeof(BucketMetaHeader))
 	{
+		ZEN_WARN("Failed to read sidecar file '{}'. Minimum size {} expected, actual size: ",
+				 SidecarPath,
+				 sizeof(BucketMetaHeader),
+				 FileSize);
 		return false;
 	}
 
@@ -535,17 +540,25 @@ BucketManifestSerializer::ReadSidecarFile(RwLock::ExclusiveLockScope&								  B
 
 	if (!Header.IsValid())
 	{
+		ZEN_WARN("Failed to read sidecar file '{}'. Header is invalid", SidecarPath);
 		return false;
 	}
 
 	if (Header.Version != BucketMetaHeader::Version1)
 	{
+		ZEN_WARN("Failed to read sidecar file '{}'. Unsupported version: {}", SidecarPath, Header.Version);
 		return false;
 	}
 
 	const uint64_t ExpectedEntryCount = (FileSize - sizeof(sizeof(BucketMetaHeader))) / sizeof(ManifestData);
 	if (Header.EntryCount > ExpectedEntryCount)
 	{
+		ZEN_WARN(
+			"Failed to read sidecar file '{}'. File is not large enough to hold expected entry count. Header count: {}, file size count: "
+			"{}",
+			SidecarPath,
+			Header.EntryCount,
+			ExpectedEntryCount);
 		return false;
 	}