private VersionedItem ReadMetadata(string id)
{
ConcurrentMetadata innerItem = _innerStore.ReadMetadata(id);
if (innerItem == null)
{
return(null);
}
return(new VersionedItem(innerItem.ETag, GetVersion(innerItem.Metadata)));
}
private void DeleteIfLatest(IConcurrentMetadataTextStore store, ConcurrentMetadata blob)
{
bool deleted = false;
string previousETag = null;
ConcurrentMetadata currentItem;
for (currentItem = blob;
!deleted && currentItem != null;
currentItem = store.ReadMetadata(blob.Id))
{
string currentETag = currentItem.ETag;
// Prevent an infinite loop if _innerStore erroneously returns false from TryDelete when a retry won't
// help. (The inner store should throw rather than return false in that case.)
if (currentETag == previousETag)
{
throw new InvalidOperationException("The operation stopped making progress.");
}
previousETag = currentETag;
deleted = _functionsStore.TryDelete(blob.Id, blob.ETag);
}
}