/// <reference types="node" />
import { BlobStoreInterface } from "@cocalc/frontend/jupyter/project-interface";
import { Router } from "express";
export declare class BlobStore implements BlobStoreInterface {
    private db;
    private stmt_insert;
    private stmt_update;
    private stmt_get;
    private stmt_data;
    private stmt_ipynb;
    private stmt_keys;
    constructor();
    init(): void;
    private init_table;
    private init_statements;
    private clean;
    private clean_old;
    private clean_filesize;
    delete_all_blobs(): void;
    save(data: any, type: any, ipynb?: any): string;
    readFile(path: string, type: string): Promise<string>;
    get(sha1: string): undefined | Buffer;
    get_ipynb(sha1: string): any;
    keys(): string[];
    express_router(base: any): Router;
}
export declare function get_blob_store(): BlobStore | undefined;