Function retryWithBackoff

apps/api/src/lib/email/email.utils.ts:178–205

(
  fn: () => Promise<T>,
  options: IRetryOptions = {}
)

 * the first attempt so the caller can react quickly.
 */
export const retryWithBackoff = async <T>(
  fn: () => Promise<T>,
  options: IRetryOptions = {}
): Promise<T> => {
  const config: IResolvedRetryOptions = { ...RETRY_DEFAULTS, ...options };
  let lastError: unknown;

  for (let attempt = 0; attempt <= config.maxRetries; attempt++) {
    try {
      return await fn();
    } catch (error: unknown) {
      lastError = error;

      if (
        attempt === config.maxRetries ||
        !isRetryableError(error, config.retryableErrorTypes)
      ) {
        throw error;
      }

      const delayMs = config.retryDelayMs * Math.pow(2, attempt);

      await delay(delayMs);
    }
  }

  throw lastError;
};

/*
 * ---------------------------------------------------------------------------