NewDiskKV creates a DiskKV that puts/gets pre-images as files in the given directory path.

ErrAlreadyExists is returned when a pre-image already exists in the KV store.

ErrNotFound is returned when a pre-image cannot be found in the KV store.

DiskKV is a disk-backed key-value store, every key-value pair is a hex-encoded .txt file, with the value as content.

MemKV implements the KV store interface in memory, backed by a regular Go map.

KV is a Key-Value store interface for pre-image data.