StorageConfig - API reference

isOwnerWithinQuota

readonly isOwnerWithinQuota: (ownerId: string & Brand<"Id"> & Brand<"OwnerId">, requiredBytes: number & Brand<"NonNaN"> & Brand<"Finite"> & Brand<"Int"> & Brand<"NonNegative"> & Brand<"Positive">) => Awaitable<boolean>;

Defined in: packages/common/src/local-first/Storage.ts:98

Callback called before an attempt to write, to check if an OwnerId has sufficient quota for the write.

The callback receives the OwnerId and the total bytes that would be stored after the write (current stored bytes plus incoming bytes), and returns a Awaitable boolean: true to allow the write, or false to deny it due to quota limits.

The callback can be synchronous (for SQLite or in-memory checks) or asynchronous (for calling remote APIs).

The callback returns a boolean rather than an error because error handling and logging are the responsibility of the callback implementation.

Relay deployments configure this callback. Client applications can observe a denied relay write as a ProtocolQuotaError by subscribing once to the shared EvoluErrorDep.evoluError store returned by createEvoluDeps.

Example

import {
  createAppOwner,
  createOwnerSecret,
  createRandomBytes,
  PositiveInt,
} from "@evolu/common";
import type { StorageConfig } from "@evolu/common/local-first";

// Create once, persist the mnemonic securely, and restore it on later runs.
const appOwner = createAppOwner(
  createOwnerSecret({ randomBytes: createRandomBytes() }),
);
const maxBytes = PositiveInt.orThrow(1024);
const relayStorageConfig: StorageConfig = {
  isOwnerWithinQuota: (ownerId, requiredBytes) =>
    ownerId === appOwner.id && requiredBytes <= maxBytes,
};

expect(
  await relayStorageConfig.isOwnerWithinQuota(
    appOwner.id,
    PositiveInt.orThrow(2048),
  ),
).toBe(false);

Extended by

Properties

isOwnerWithinQuota

Example