src/utils/AsyncLock.ts

   1 // Partial Copyright Jerome Benoit. 2021-2023. All Rights Reserved.
   2
   3 export enum AsyncLockType {
   4   configuration = 'configuration',
   5   performance = 'performance',
   6 }
   7
   8 export class AsyncLock {
   9   private static readonly asyncLocks = new Map<AsyncLockType, AsyncLock>();
  10   private acquired: boolean;
  11   private readonly resolveQueue: ((value: void | PromiseLike<void>) => void)[];
  12
  13   private constructor(private readonly type: AsyncLockType) {
  14     this.acquired = false;
  15     this.resolveQueue = [];
  16   }
  17
  18   public static async acquire(type: AsyncLockType): Promise<void> {
  19     const asyncLock = AsyncLock.getAsyncLock(type);
  20     if (!asyncLock.acquired) {
  21       asyncLock.acquired = true;
  22     } else {
  23       return new Promise((resolve) => {
  24         asyncLock.resolveQueue.push(resolve);
  25       });
  26     }
  27   }
  28
  29   public static async release(type: AsyncLockType): Promise<void> {
  30     const asyncLock = AsyncLock.getAsyncLock(type);
  31     if (asyncLock.resolveQueue.length === 0 && asyncLock.acquired) {
  32       asyncLock.acquired = false;
  33       return;
  34     }
  35     const queuedResolve = asyncLock.resolveQueue.shift();
  36     return new Promise((resolve) => {
  37       queuedResolve();
  38       resolve();
  39     });
  40   }
  41
  42   private static getAsyncLock(type: AsyncLockType): AsyncLock {
  43     if (!AsyncLock.asyncLocks.has(type)) {
  44       AsyncLock.asyncLocks.set(type, new AsyncLock(type));
  45     }
  46     return AsyncLock.asyncLocks.get(type);
  47   }
  48 }