@atton16/cluster-lock

A lock implementation for both single-thread and clustered Node.JS environment.

This is the simple lock implementation and might not be suitable for production application.

Installation

npm install @atton16/cluster-lock

Usage

Single Process

import { Lock } from '@atton16/cluster-lock';

const lock = new Lock('read-car');

lock.acquire().then(() => {
  console.log('I can now read car!');
  lock.release();
});

Cluster

import cluter from 'cluster';
import { Lock } from '@atton16/cluster-lock';

if (cluster.isMaster) {
  const lock = new Lock('read-car'); // master lock instance is required
  cluster.fork();  // worker 1
  cluster.fork();  // worker 2
  // NOTE: master process can also acquire lock
  lock.acquire().then(() => {
    console.log('I can now read car!');
    lock.release();
  });
} else {
  const lock = new Lock('read-car');

  lock.acquire().then(() => {
    console.log('I can now read car!');
    lock.release();
  });
}

Limitations

1. Master lock instance is required in cluster mode.
2. Same-name lock is supported in worker process only (which runs in cluster mode).

License

ISC License

Copyright (c) 2020, Attawit Kittikrairit

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.