@statesync/persistence

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@statesync/persistence / StorageBackendWithMetadata

Interface: StorageBackendWithMetadata<T>

Defined in: persistence/src/types.ts:204

Extended storage backend that persists metadata alongside snapshots.

Backends implementing this interface support schema versioning, TTL expiration, integrity hashing, and storage usage reporting.

The persistence applier automatically detects this interface via duck typing and uses the metadata-aware methods when available.

Extends

• StorageBackend<T>

Type Parameters

Type Parameter	Description
T	The shape of the application state.

Methods

clear()?

optional clear(): Promise<void>;

Defined in: persistence/src/types.ts:190

Remove all persisted data from this backend's storage key.

This method is optional -- not all backends support clearing.

Returns

Promise<void>

A promise that resolves when the data has been removed.

Inherited from

StorageBackend.clear

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getUsage()?

optional getUsage(): Promise<StorageUsage>;

Defined in: persistence/src/types.ts:227

Estimate current storage usage for this backend.

This method is optional -- not all backends can report usage.

Returns

Promise<StorageUsage>

Storage usage information including bytes used and quota (if available).

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load()

load(): Promise<SnapshotEnvelope<T> | null>;

Defined in: persistence/src/types.ts:181

Load the most recent snapshot from persistent storage.

Returns

Promise<SnapshotEnvelope<T> | null>

The stored snapshot, or null if no snapshot has been persisted yet.

Inherited from

StorageBackend.load

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loadWithMetadata()

loadWithMetadata(): Promise<PersistedSnapshot<T> | null>;

Defined in: persistence/src/types.ts:218

Load the most recent snapshot along with its metadata.

Returns

Promise<PersistedSnapshot<T> | null>

The stored snapshot and metadata bundle, or null if nothing is persisted.

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save()

save(snapshot): Promise<void>;

Defined in: persistence/src/types.ts:174

Save a snapshot to persistent storage.

Parameters

Parameter	Type	Description
snapshot	SnapshotEnvelope<T>	The snapshot envelope to persist.

Returns

Promise<void>

A promise that resolves when the write is complete.

Inherited from

StorageBackend.save

---

saveWithMetadata()

saveWithMetadata(data): Promise<void>;

Defined in: persistence/src/types.ts:211

Save a snapshot together with its metadata to persistent storage.

Parameters

Parameter	Type	Description
data	PersistedSnapshot<T>	The snapshot and metadata bundle to persist.

Returns

Promise<void>

A promise that resolves when the write is complete.