locking_in_javascript_5.cs

  import { Mutex } from 'async-mutex';
  private mutex = new Mutex();
  loadWithMutexLock = async (key: string): Promise<boolean> => {
    this.log(key + 'Calling loadWithMutexLock');
    const random = Math.random();
    this.log(key + 'Random: ' + random);

    // Check if the data is already loaded
    if (this.mutexDataMap.has(key)) {
      this.log(key + 'Data is already loaded');
      return true;
    }

    return this.mutex.runExclusive(async () => {
        // Check again inside the mutex to avoid race conditions
        if (this.mutexDataMap.has(key)) {
          this.log(key + 'InsideMutex: Data is already loaded');
          return true;
        }

        this.log(key + '***START*** Loading data');
        await this.slowApiCall(key);

        this.mutexDataMap.set(key, 'data + ' + random);
        this.log(key + '***END*** Data loaded');
        return true;
    });
  }