node-etcd-lock


Distributed locks powered by etcd v3 for Node.js.

Installation

``shell
npm install node-etcd-lock
`

Usage

`js
'use strict'
const assert = require('assert')
const Locker = require('node-etcd-lock')

const locker = new Locker({ address: '127.0.0.1:2379' })

;(async function () {
// Acquire a lock for a specified recource.
const lock = await locker.lock('resource_key', 3 * 1000)
// This lock will be acquired after 3000 ms.
const anotherLock = await locker.lock('resource_key', 3 * 1000)
// Unlock the lock manually.
await anotherLock.unlock()

assert((await locker.isLocked('resource_key')) === false)
})(console.error)
`

API

Class Locker

$3

- address String: The address of etcd(v3) server, by default is '127.0.0.1:2379'
- defaultTimeout Number: Milliseconds of lock's default timeout, by default is 5000.
- etcdKeyPrefix String: Prefix of the keys of locks in etcd, by default is '__etcd_lock/'.
- rootCerts, privateKey, certChain Buffer: Options to create a GRPC SSL Credentials object, see https://grpc.io/grpc/node/src_credentials.js.html#line85.

$3

- keyName String: The key of the resource to lock.
- timeout Number: Milliseconds of the lock's timeout.

Lock the resource with keyName, return a Promise which will be resolved with a Lock instance when the resource is available.

$3

- keyName String: The key of the resource which need to be checked.

Check whether the resource with keyName` has already been locked.

Class Lock

$3

Unlock this lock immediately.