2025-04-19 15:38:48 +08:00

56 lines
1.4 KiB
TypeScript

import { bytesToUnprefixedHex } from './bytes.js'
import type { BatchDBOp, DB, DBObject } from './db.js'
export class MapDB<
TKey extends Uint8Array | string | number,
TValue extends Uint8Array | string | DBObject
> implements DB<TKey, TValue>
{
_database: Map<TKey, TValue>
constructor(database?: Map<TKey, TValue>) {
this._database = database ?? new Map<TKey, TValue>()
}
async get(key: TKey): Promise<TValue | undefined> {
const dbKey = key instanceof Uint8Array ? bytesToUnprefixedHex(key) : key.toString()
return this._database.get(dbKey as TKey)
}
async put(key: TKey, val: TValue): Promise<void> {
const dbKey = key instanceof Uint8Array ? bytesToUnprefixedHex(key) : key.toString()
this._database.set(dbKey as TKey, val)
}
async del(key: TKey): Promise<void> {
const dbKey = key instanceof Uint8Array ? bytesToUnprefixedHex(key) : key.toString()
this._database.delete(dbKey as TKey)
}
async batch(opStack: BatchDBOp<TKey, TValue>[]): Promise<void> {
for (const op of opStack) {
if (op.type === 'del') {
await this.del(op.key)
}
if (op.type === 'put') {
await this.put(op.key, op.value)
}
}
}
/**
* Note that the returned shallow copy will share the underlying database with the original
*
* @returns DB
*/
shallowCopy(): DB<TKey, TValue> {
return new MapDB<TKey, TValue>(this._database)
}
open() {
return Promise.resolve()
}
}