@tslock/in-memory

In-memory lock provider for TSLock — testing and local development only.

⚠️ Not for production distributed locking. This provider locks only within a single Node.js process. Multiple instances of your application will each have their own Map and will not coordinate. Use this for unit tests, local development, and single-process demos. For any deployment with more than one instance, use a real distributed backend — see the provider matrix.

A TSLock provider backed by a plain Map<string, number>. Node.js is single-threaded, so no synchronization is needed. It implements ExtensibleLockProvider, so it supports extend().

Installation

pnpm add @tslock/core @tslock/in-memory

Usage

import { createLockConfig, DefaultLockingTaskExecutor } from '@tslock/core';
import { InMemoryLockProvider } from '@tslock/in-memory';

const provider = new InMemoryLockProvider();
const executor = new DefaultLockingTaskExecutor(provider);

await executor.executeWithLock(
  () => myScheduledTask(),
  createLockConfig({ name: 'my-task', lockAtMostFor: '5m', lockAtLeastFor: '1m' }),
);

It's also handy for unit-testing code that depends on a LockProvider without standing up a real backend:

const provider = new InMemoryLockProvider();
provider.isLocked('my-task'); // false until a lock is held

Integration tests

The in-memory provider runs the shared lock, extension, and fuzz contracts without external services:

pnpm --filter @tslock/in-memory test:integration

Requirements

• Node.js >= 22

License

Apache 2.0 — see LICENSE for details.