/// <reference types="node" />
import * as Koa from 'koa';
import * as NodeCache from 'node-cache';
export declare const nodeCache: NodeCache;
export declare class DatastoreCache {
    /** 缓存响应结果 */
    cacheResponse(key: string, headers: {}, payload: Buffer | object): Promise<void>;
    /** 清空全部的响应缓存 */
    clearCache(type?: 'Page' | 'Spider' | 'Crawler', urlOrHash?: string): Promise<void>;
    /**
     * Returns middleware function.
     */
    middleware(): (ctx: Koa.Context, next: () => Promise<unknown>) => Promise<void>;
}