Shared read locks and exclusive write locks: Concurrent access for read-only operations, exclusive access for write operations.
import Lock from 'shared-exclusive-lock'
const lock = new Lock()
// Multiple read locks at the same time:
const releaseReadLock1 = await lock.readLock()
const releaseReadLock2 = await lock.readLock()
// Write lock is granted as soon as all existing read locks have been released:
lock.writeLock().then((releaseWriteLock) => releaseWriteLock())
// As soon as a write lock is queued, no further read locks are granted in parallel:
lock.readLock().then((releaseReadLock3) => releaseReadLock3())
releaseReadLock1()
releaseReadLock2()
// Sequence:
// 1. Receive first read lock.
// 2. Receive second read lock.
// 3. Release first read lock.
// 4. Release second read lock.
// 5. Receive write lock.
// 6. Release write lock.
// 7. Receive third read lock.
// 8. Release third read lock.This is a Node.js module available through the npm registry.
You can install the module via the npm install command:
$ npm install shared-exclusive-lock --save
Copyright (c) 2017-2018 Sebastian Schmidt
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