import type { App } from "../main.js";
export declare const METADATA_COLLECTION_NAME = "_metadata";
export default class Metadata {
    db_collection_name: string;
    app: App;
    constructor(app: App);
    get(key: string | number): Promise<unknown>;
    set(key: string, value: string | number): Promise<void>;
    clear(): Promise<import("mongodb").DeleteResult>;
}