@types/async-lock

constructor

constructor(options?: AsyncLock.AsyncLockOptions);

property DEFAULT_MAX_OCCUPATION_TIME

static readonly DEFAULT_MAX_OCCUPATION_TIME: number;

property DEFAULT_MAX_PENDING

static readonly DEFAULT_MAX_PENDING: number;

property DEFAULT_TIMEOUT

static readonly DEFAULT_TIMEOUT: number;

method acquire

acquire: {
    <T>(
        key: string | string[],
        fn:
            | (() => T | PromiseLike<T>)
            | ((done: AsyncLock.AsyncLockDoneCallback<T>) => any),
        opts?: AsyncLock.AsyncLockOptions
    ): Promise<T>;
    <T>(
        key: string | string[],
        fn: (done: AsyncLock.AsyncLockDoneCallback<T>) => any,
        cb: AsyncLock.AsyncLockDoneCallback<T>,
        opts?: AsyncLock.AsyncLockOptions
    ): void;
};

• Lock on asynchronous code.

  Parameter key

  resource key or keys to lock

  Parameter fn

  function to execute

  Parameter opts

  options

  Example 1

  import AsyncLock = require('async-lock'); const lock = new AsyncLock();

  lock.acquire( key, () => { // return value or promise }, opts ).then(() => { // lock released });

• Lock on asynchronous code.

  Parameter key

  resource key or keys to lock

  Parameter fn

  function to execute

  Parameter cb

  callback function

  Parameter opts

  options

  Example 1

  import AsyncLock = require('async-lock'); const lock = new AsyncLock();

  lock.acquire( key, (done) => { // async work done(err, ret); }, (err, ret) => { // lock released }, opts );

method isBusy

isBusy: (key?: string) => boolean;

• Whether there is any running or pending async function.

property domainReentrant

domainReentrant?: boolean | undefined;

• Make a lock reentrant in the same domain.

  false

  Example 1

  import AsyncLock = require('async-lock'); import * as domain from 'domain';

  const lock = new AsyncLock({ domainReentrant: true }); const d = domain.create(); d.run(() => { lock.acquire('key', () => { // Enter lock return lock.acquire('key', () => { // Enter same lock twice }); }); });

property maxOccupationTime

maxOccupationTime?: number | undefined;

• Max amount of time allowed between entering the queue and completing execution.

  0 (Never)

property maxPending

maxPending?: number | undefined;

• Max number of tasks allowed in the queue at a time.

  1000

property Promise

Promise?: unknown;

• Use your own promise library instead of the global Promise variable.

  Example 1

  import AsyncLock = require('async-lock'); import Bluebird = require('bluebird'); import Q = require('q');

  new AsyncLock({ Promise: Bluebird }); // Bluebird new AsyncLock({ Promise: Q }); // Q

property skipQueue

skipQueue?: boolean | undefined;

• Allows to enqueue a task in the front of the queue, skipping all enqueued tasks.

  false

  Example 1

  import AsyncLock = require('async-lock');

  const lock = new AsyncLock(); // Add a task to the front of the queue waiting for a given lock lock.acquire(key, fn1, cb); // runs immediately lock.acquire(key, fn2, cb); // added to queue lock.acquire(key, priorityFn, cb, { skipQueue: true }); // jumps queue and runs before fn2

property timeout

timeout?: number | undefined;

• Max amount of time an item can remain in the queue before acquiring the lock.

  0 (Never)