Widely available Supported across all major browsers. Safe to use in production.

Locks

The Lock interface of the Web Locks API provides the name and mode of a lock. This may be a newly requested lock that is received in the callback to LockManager.request(), or a record of an active or queued lock returned by LockManager.query().

Storage

Browser support

Feature Desktop Mobile
Chrome
Edge
Firefox
Safari
Chrome Android
Safari iOS
Lock
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mode

The mode read-only property of the Lock interface returns the access mode passed to LockManager.request() when the lock was requested. The mode is either "exclusive" (the default) or "shared".
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name

The name read-only property of the Lock interface returns the name passed to LockManager.request selected when the lock was requested.
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LockManager

The LockManager interface of the Web Locks API provides methods for requesting a new Lock object and querying for an existing Lock object. To get an instance of LockManager, call navigator.locks.
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query

The query() method of the LockManager interface returns a Promise that resolves with an object containing information about held and pending locks.
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request

The request() method of the LockManager interface requests a Lock object with parameters specifying its name and characteristics. The requested Lock is passed to a callback, while the function itself returns a Promise that resolves (or rejects) with the result of the callback after the lock is released, or rejects if the request is aborted.
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locks

The locks read-only property of the Navigator interface returns a LockManager object which provides methods for requesting a new Lock object and querying for an existing Lock object.
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locks

The locks read-only property of the WorkerNavigator interface returns a LockManager object which provides methods for requesting a new Lock object and querying for an existing Lock object.
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1+Supported (version) Not supported ※Has note Sub-feature descriptions sourced from MDN Web Docs (CC BY-SA 2.5)

Syntax

JAVASCRIPT 
navigator.locks.request("net_db_sync", showLockProperties);
navigator.locks.request("another_lock", { mode: "shared" }, showLockProperties);

function showLockProperties(lock) {
  console.log(`The lock name is: ${lock.name}`);
  console.log(`The lock mode is: ${lock.mode}`);
}

Use cases

  • Using Locks

    The Lock interface of the Web Locks API provides the name and mode of a lock.

Cautions

  • May not be supported in older browsers.

Implementation notes

  • Some APIs require a secure context (HTTPS) or user activation. Check the requirements before use.

Related links