import { IAuthClass } from "./auth-class";
import { Callback, IServiceAccountCreds } from "../utils/type_alias";
export declare class ServiceAccount implements IAuthClass {
    private token;
    private googleAuth;
    private JWTClient;
    constructor(creds: IServiceAccountCreds, googleAuthScopes?: string[]);
    readonly authClient: any;
    authorize(callback?: Callback<any>): void;
    isAuthorized(): boolean;
    ensureValid(callback?: Callback<any>): void;
}