LockManager: query() method

{{APIRef("Web Locks API")}}{{securecontext_header}} {{AvailableInWorkers}}

The query() method of the {{domxref("LockManager")}} interface returns a {{jsxref('Promise')}} that resolves with an object containing information about held and pending locks.

Syntax

query()

Parameters

None.

Return value

A {{jsxref('Promise')}} that resolves with an object containing a snapshot of the {{domxref("LockManager")}} state. The object has the following properties:

• held
  • : An array of LockInfo objects for held locks.
• pending
  • : An array of LockInfo objects for pending lock requests.

The LockInfo object can have the following properties:

• name
  • : The name passed to {{domxref("LockManager.request()")}} when the lock was requested.
• mode
  • : The access mode passed to {{domxref("LockManager.request()")}} when the lock was requested. The mode is either "exclusive" or "shared".
• clientId
  • : The unique identity of the context where {{domxref("LockManager.request()")}} is called. This is the same value as {{domxref("Client.id")}}.

Exceptions

This method may return a promise rejected with a {{domxref("DOMException")}} of one of the following types:

• InvalidStateError {{domxref("DOMException")}}
  • : Thrown if the environments document is not fully active.
• SecurityError {{domxref("DOMException")}}
  • : Thrown if a lock manager cannot be obtained for the current environment.

Examples

const state = await navigator.locks.query();
for (const lock of state.held) {
  console.log(`held lock: name ${lock.name}, mode ${lock.mode}`);
}
for (const request of state.pending) {
  console.log(`requested lock: name ${request.name}, mode ${request.mode}`);
}

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}