import type { Request, Response, NextFunction } from "express";
declare const Rules: {
    DELAY: typeof delay;
    HTTPERROR: typeof httpError;
    EXCEPTION: typeof exception;
};
type UserOptions = {
    seed?: string;
    probability?: number;
    maxDelay?: number;
    errCodes?: number[];
    rules?: Function[];
};
/**
 * Requests slowdown
 * @param req - express request
 * @param res - express response
 * @param next - express next function
 */
declare function delay(req: Request, res: Response, next: NextFunction): Promise<void>;
/**
 * Random response error
 * @param req - express request
 * @param res - express response
 */
declare function httpError(req: Request, res: Response): void;
/**
 * Throw random exception
 */
declare function exception(): void;
/**
 * Randomly throw error and slow response
 * @param options - user options
 * @returns a chaos middleware instance
 */
declare function chaos(options?: UserOptions): (req: Request, res: Response, next: NextFunction) => any;
export { chaos, Rules };