browser-tabs-lock

What is browser-tabs-lock?

The browser-tabs-lock npm package provides a mechanism to ensure that only one tab of a web application is active at a time. This is useful for preventing race conditions and ensuring data consistency when multiple tabs are open.

What are browser-tabs-lock's main functionalities?

Acquire a Lock

This feature allows you to acquire a lock with a specified key. If the lock is successfully acquired, you can perform operations that require the lock and then release it.

const { acquireLock } = require('browser-tabs-lock');

async function main() {
  const lock = await acquireLock('my-lock');
  if (lock) {
    console.log('Lock acquired');
    // Perform operations that require the lock
    lock.release();
  } else {
    console.log('Failed to acquire lock');
  }
}

main();

Release a Lock

This feature allows you to release a previously acquired lock. This is important to ensure that other tabs can acquire the lock when needed.

const { acquireLock } = require('browser-tabs-lock');

async function main() {
  const lock = await acquireLock('my-lock');
  if (lock) {
    console.log('Lock acquired');
    // Perform operations that require the lock
    lock.release();
    console.log('Lock released');
  } else {
    console.log('Failed to acquire lock');
  }
}

main();

Check Lock Status

This feature allows you to check if a lock with a specified key is currently acquired. This can be useful for debugging or for conditional logic based on lock status.

const { isLockAcquired } = require('browser-tabs-lock');

async function main() {
  const lockAcquired = await isLockAcquired('my-lock');
  if (lockAcquired) {
    console.log('Lock is currently acquired');
  } else {
    console.log('Lock is not acquired');
  }
}

main();

Other packages similar to browser-tabs-lock

localforage

LocalForage is a fast and simple storage library for JavaScript. While it is primarily used for offline storage, it can be used to implement similar locking mechanisms by storing lock states in the local storage. However, it does not provide built-in locking mechanisms like browser-tabs-lock.

idb-keyval

idb-keyval is a small library that provides a simple key-value store backed by IndexedDB. Similar to LocalForage, it can be used to implement custom locking mechanisms by storing lock states, but it does not offer built-in support for locks.

broadcast-channel

Broadcast Channel is a library that allows simple communication between browser tabs or workers. It can be used to implement custom locking mechanisms by broadcasting lock states between tabs, but it does not provide built-in lock management like browser-tabs-lock.

README

Browser Tabs Lock

Using this package, you can easily get lock functionality across tabs on all modern browsers.

Some things to note about:

• This is not a reentrant lock. So please do not attempt to acquire a lock on the same key within the same tab if you are already currently holding that lock.
• Theoretically speaking, it is impossible to have foolproof locking built on top of javascript in the browser. One can only make it so that in all practical scenarios, it emulates locking.

Installation:

npm i --save browser-tabs-lock

Usage in an async function:

import Lock from "browser-tabs-lock";

let lock = new Lock()
async function lockingIsFun() {
	if (await lock.acquireLock("hello", 5000)) {
		// lock has been acquired... we can do anything we want now.
		// ...
		lock.releaseLock("hello");
	} else {
		// failed to acquire lock after trying for 5 seconds. 
	}
}

Usage using callbacks:

import Lock from "browser-tabs-lock";

let lock = new Lock()
lock.acquireLock("hello", 5000).then((success) => {
	if (success) {
		// lock has been acquired... we can do anything we want now.
		// ...
		lock.releaseLock("hello");
	} else {
		// failed to acquire lock after trying for 5 seconds. 
	}
});

Also note, that if your web app only needs to work on google chrome, you can use the Web Locks API instead. This probably has true locking!

Support, questions and bugs

For now, we are most reachable via [e-mail] and via the GitHub issues feature

Authors

Created with :heart: by the folks at SuperTokens. We are a startup passionate about security and solving software challenges in a way that's helpful for everyone! Please feel free to give us feedback at [e-mail], until our website is ready :grinning: