StorageAdapter

StorageAdapter is the interface webauthn-server-buildkit uses to read and write all persistent data. It has four sections — users, credentials, challenges, and sessions — each a set of async methods. See the Storage adapters guide for implementation notes.

MemoryStorageAdapter

A ready-made in-memory implementation, exported for development and tests:

import { MemoryStorageAdapter } from 'webauthn-server-buildkit';
const storage = new MemoryStorageAdapter();

State is per-process and lost on restart — not for production.

users

Method	Signature
findById	(id: string | number) => Promise<UserModel | null>
findByUsername	(username: string) => Promise<UserModel | null>
create	(user: Omit<UserModel, 'id'>) => Promise<UserModel>
update	(id, updates: Partial<UserModel>) => Promise<UserModel | null>
delete	(id) => Promise<boolean>

credentials

Method	Signature
findById	(id: Base64URLString) => Promise<WebAuthnCredential | null>
findByUserId	(userId) => Promise<WebAuthnCredential[]>
findByWebAuthnUserId	(webAuthnUserId: Base64URLString) => Promise<WebAuthnCredential[]>
create	(credential: Omit<WebAuthnCredential, 'createdAt'>) => Promise<WebAuthnCredential>
updateCounter	(id, counter: number) => Promise<boolean>
updateLastUsed	(id) => Promise<boolean>
delete	(id) => Promise<boolean>
deleteByUserId	(userId) => Promise<boolean>

challenges

Method	Signature
create	(challenge: ChallengeData) => Promise<boolean>
find	(challenge: string) => Promise<ChallengeData | null>
delete	(challenge: string) => Promise<boolean>
deleteExpired	() => Promise<boolean>

sessions

Method	Signature
create	(sessionId: string, data: SessionData) => Promise<boolean>
find	(sessionId: string) => Promise<SessionData | null>
update	(sessionId, data: Partial<SessionData>) => Promise<boolean>
delete	(sessionId) => Promise<boolean>
deleteExpired	() => Promise<boolean>
deleteByUserId	(userId) => Promise<boolean>

Contracts

• find* methods return null (never throw) when a record is absent.
• WebAuthnCredential.publicKey is a Uint8Array — round-trip it byte-for-byte.
• Index credentials.id and credentials.webAuthnUserID for ceremony performance.