lock

The lock function ensures that an asynchronous function is not executed simultaneously, allowing calls to be queued or rejected according to configuration.

Syntax

lock(callback, options?)

Parameters

Name	Type	Description
callback	Function	Asynchronous function to be protected by the lock.
options	object	(Optional) Settings: { queue, onLocked, onError }.

options object

Name	Type	Description
queue	boolean	If true, calls during the lock are queued (default: true).
onLocked	Function	Function called when a call is blocked.
onError	Function	Function called in case of an error during callback execution.

Return Value

Type	Description
Function	Asynchronous function that respects the lock and the configured options.

Examples

const lockedFn = lock(async () => {
  await sleep(100);
  console.log('Executed!');
});

lockedFn();
lockedFn(); // Executes in sequence, not simultaneously

Notes

• Throws an error if the callback is not a function.
• Useful for avoiding race conditions in asynchronous operations.

References

• MDN: Promise