Await Locker

awaitLocker.ts

export class AwaitLocker {
  private static lockerCallbacks: {[key: string]: {callback?: () => void}[]} = {};
  static async startLock(key: string) {
    if (!AwaitLocker.lockerCallbacks[key]) {
      AwaitLocker.lockerCallbacks[key] = [];
    }

    if (AwaitLocker.lockerCallbacks[key].length > 0) {
      let callback: () => void;
      const promise = new Promise<void>((res) => {
        callback = res;
      });
      AwaitLocker.lockerCallbacks[key].push({callback: callback!});
      await promise;
    } else {
      AwaitLocker.lockerCallbacks[key].push({callback: undefined});
    }
  }

  static async releaseLock(key: string) {
    // NEVER AWAIT THIS
    if (!AwaitLocker.lockerCallbacks[key]) {
      AwaitLocker.lockerCallbacks[key] = [];
    }

    AwaitLocker.lockerCallbacks[key] = AwaitLocker.lockerCallbacks[key].slice(1);

    if (AwaitLocker.lockerCallbacks[key].length > 0) {
      AwaitLocker.lockerCallbacks[key][0].callback?.();
    }
  }
}