Time Attack Mittigator - function that exeutes the job, with minimum time needed for answer, even if the job finished earlier

time-attack-mitigator.ts

/**
 * This function will execute the job, but return the value from it when at least `timeout` amount of milliseconds passed  

 * @param {() => Promise<T>} job
 * @param {number} timeout
 * @returns {Promise<T>}
 */
export async function TimeAttackMitigator<T>(job: () => Promise<T>, timeout = 700): Promise<T> {
  return new Promise<T>((resolve, reject) => {
    let canResolve = false;
    let state: boolean | undefined;
    let value: T;
    let error: any;
    
    const tryFinish = () => {
      if (canResolve) {
        if (state === true) {
          canResolve = false;
          
          resolve(value);
        } else if (state === false) {
          canResolve = false;
          
          reject(error);
        }
      }
    };
    setTimeout(() => {
      canResolve = true;
      
      tryFinish();
    }, timeout);
    
    job().then((arg: T) => {
      state = true;
      value = arg;
      
      tryFinish();
    }).catch((err) => {
      state = false;
      error = err;
      
      tryFinish();
    });
  });
}