Adapter account persistence
Implementing an Auth.js database adapter that stores and retrieves linked provider accounts.
Auth.js · Type Alias
AdapterAccount
AdapterAccount describes an account record managed by an Auth.js adapter. It links a user to a provider and carries the provider-specific account identity used by adapter operations.
How it works
AdapterAccount is the adapter-facing account shape for connecting a user with an authentication provider. It includes the provider-specific identity, account kind, and owning user, while also allowing account token data inherited from the broader Account model.
Syntax
type AdapterAccount = Account & { userId: string }Returns
An adapter account record describing a user’s connection to a provider.
Key points
- The type models the relationship between an Auth.js user and an authentication provider.
- The documentation distinguishes account categories including OAuth/OIDC and email accounts.
- OAuth/OIDC account records are created during sign-in through an OAuth provider.
- Email-provider sign-ins create the corresponding email account record.
- Adapter account retrieval identifies a record using both its provider account ID and provider.
- The provider field identifies which authentication provider owns the connection.
Common mistakes
- Adapter lookup methods may return null when no matching account exists; do not treat a missing account as an AdapterAccount.
- Do not assume a user has only one AdapterAccount; account records represent separate provider connections.
Example: Define an adapter account
import type { AdapterAccount } from "next-auth/adapters"
const account: AdapterAccount = {
provider: "google",
providerAccountId: "user-123",
type: "oauth",
userId: "user-456",
}
export function getAccount(): AdapterAccount {
return account
}This typed object represents an adapter-managed account linked to a user and an authentication provider.
When to use it
Typed account lookup
Typing account data returned by an adapter’s provider-account lookup.
Multiple provider connections
Representing multiple OAuth, OIDC, or email connections for one user.
Interview questions
QWhat does AdapterAccount represent?
AdapterAccount is the account type used by Auth.js adapters. It models a provider connection belonging to a user and is returned by adapter operations such as getAccount.
Follow-up: How should getAccount signal that no record exists? It should return null rather than fabricate an AdapterAccount.
QCan one user have multiple AdapterAccount values?
An account connects a user to a provider. Auth.js documents OAuth/OIDC and email accounts as account categories, and one user may have several accounts.
Follow-up: Why is provider identity needed? It distinguishes the same user’s separate external or authentication-provider connections.
QHow is AdapterAccount used by an adapter?
AdapterAccount is related to Account and carries provider information plus adapter ownership data, including the user associated with the account. Adapter methods use it when reading and writing account records.
Follow-up: Which adapter operation commonly reads it? getAccount takes a provider account ID and provider and returns an AdapterAccount or null.
Related
AccountAdapterAdapterUsergetAccountlinkAccount