import { EJSON } from 'bson';
import { CloudConfig } from '@alipay/faas-server-utils';
export declare function validateTimeout(timeout?: number | [number, number]): undefined | number | [number, number];
export declare function authString(config: CloudConfig, body?: string): string;
export declare class MongoSerializer {
    static serialize(data: any): string;
    static deserialize(data: any): EJSON.SerializableTypes;
    static filterUndefinedKey(o: any, visited: any[]): any;
}
export declare function decamelize(text: string): string;
