1681-engine / index / SaveStore

Class: SaveStore

Defined in: src/save/SaveStore.ts:68

Named save slots with a schema version, migrations from older versions, a checksum to catch a damaged slot, and a backup of the previous save to fall back to. Data must be JSON-safe (plain objects, arrays, strings, finite numbers, booleans, null).

const saves = new SaveStore({ version: 3, migrations: { 1: addInventory, 2: renameGold } });
await saves.save('slot1', state, { level: 4 });
const r = await saves.load<GameState>('slot1');
if (r.ok) start(r.data); else if (r.reason !== 'missing') warn(r.reason);

Writes to one slot are queued in order, so an autosave and a manual save never land the wrong way round.

Constructors

Constructor

new SaveStore(options): SaveStore;

Defined in: src/save/SaveStore.ts:77

Parameters

Parameter	Type
options	SaveStoreOptions

Returns

SaveStore

Properties

version

readonly version: number;

Defined in: src/save/SaveStore.ts:69

Methods

delete()

delete(slot): Promise<void>;

Defined in: src/save/SaveStore.ts:117

Removes a slot and its backup.

Parameters

Parameter	Type
slot	string

Returns

Promise<void>

---

list()

list(): Promise<SaveInfo[]>;

Defined in: src/save/SaveStore.ts:126

Every slot that reads, newest first, without migrating its data. A damaged slot is left out.

Returns

Promise<SaveInfo[]>

---

load()

load<T>(slot): Promise<LoadResult<T>>;

Defined in: src/save/SaveStore.ts:106

Reads slot, brought to the current version. Never throws for a bad slot: the result says what went wrong.

Type Parameters

Type Parameter
T

Parameters

Parameter	Type
slot	string

Returns

Promise<LoadResult<T>>

---

save()

save(
   slot, 
   data, 
   meta?
): Promise<SaveInfo>;

Defined in: src/save/SaveStore.ts:88

Writes data to slot at the current version. Rejects when the backend does (a full disk, a quota).

Parameters

Parameter	Type	Default value
slot	string	undefined
data	unknown	undefined
meta	unknown	null

Returns

Promise<SaveInfo>