/**
 * 是否是ws代理请求
 * @param str
 * @returns
 */
export declare function isWS(str: string): boolean;
export declare function encodeSecAccept(seckey: string): string;
export declare function parseHeaders(str: string): {
    [key: string]: any;
};
export declare function buildRequestHeader(url: string): string;
export declare function buildResponseHeader(headers: {
    "sec-websocket-key": string;
    [key: string]: any;
}): string;