/// <summary>
/// Conditionally removes a bucket as long as it is empty of key/value pairs.
/// Condenses any surrounding buckets if necessary
/// </summary>
internal async Task <bool> PruneBucketAsync(HashManifest manifest, long bucketIndex, string bucketName, HashBucket bucket, CancellationToken cancellationToken)
{
if (bucket.Head.HasValue || bucket.Tail.HasValue)
{
return(false);
}
await StateManager.RemoveStateAsync(bucketName, cancellationToken);
if (bucket.Previous.HasValue)
{
var previousBucketName = IndexToBucket(bucket.Previous.Value);
var previousBucket = await StateManager.GetStateAsync <HashBucket>(previousBucketName, cancellationToken);
previousBucket.Next = bucket.Next;
await StateManager.SetStateAsync(previousBucketName, previousBucket, cancellationToken);
}
if (bucket.Next.HasValue)
{
var nextBucketName = IndexToBucket(bucket.Next.Value);
var nextBucket = await StateManager.GetStateAsync <HashBucket>(nextBucketName, cancellationToken);
nextBucket.Previous = bucket.Previous;
await StateManager.SetStateAsync(nextBucketName, nextBucket, cancellationToken);
}
if (manifest.Head == bucketIndex)
{
manifest.Head = bucket.Next;
}
if (manifest.Tail == bucketIndex)
{
manifest.Tail = bucket.Previous;
}
return(true);
}
protected static long NextIndex(HashManifest manifest)
{
return(manifest.Next++);
}
