ZapDB

ZapDB (github.com/luxfi/zapdb/v4) is an embeddable, persistent key-value database written in pure Go. It is the default storage engine for Lux blockchain nodes and is used by the MPC system for encrypted key share storage.

Design

ZapDB is based on the WiscKey paper, which separates keys from values in an LSM tree architecture. Keys are stored in the LSM tree (served from RAM), while values are stored in a separate value log (served from SSD). This reduces write amplification and keeps the LSM tree small.

Features

Quick Start

import "github.com/luxfi/zapdb/v4"

// Open a database
db, err := badger.Open(badger.DefaultOptions("/tmp/zapdb"))
if err != nil {
    log.Fatal(err)
}
defer db.Close()

// Write a key-value pair
err = db.Update(func(txn *badger.Txn) error {
    return txn.Set([]byte("hello"), []byte("world"))
})

// Read a key
err = db.View(func(txn *badger.Txn) error {
    item, err := txn.Get([]byte("hello"))
    if err != nil {
        return err
    }
    return item.Value(func(val []byte) error {
        fmt.Println(string(val)) // "world"
        return nil
    })
})

Use in Lux

ZapDB is the default dbType in the Lux Operator LuxNetwork CRD. Set spec.dbType: zapdb (the default) to use it as the node database backend.