import { Request, Response, NextFunction } from 'express';
import { Role, IDecoded, GatemanOptions, CreateSessionOptions, CreateHeadlessTokenOptions } from './typings';
export declare class Gateman {
    options: GatemanOptions;
    /**
     * Sets the redis object for persisting tokens, the secret key for sealing & unsealing
     *  objects and the default session duration.
     * @param options Gateman config options
     */
    constructor(options: GatemanOptions);
    /**
     * Persists a token using the user's id in Redis for a specific period of time
     * @param id The user's id
     * @param token The user's token
     * @param sessionDuration How long the token should be peristed to Redis in seconds.
     */
    private persistSession;
    /**
     * Deletes a token from Redis using the user's id
     * @param id The user's id
     */
    clearSession(id: string): Promise<number>;
    /**
     * Creates an encrypted token using the user's id and role, and persists it to Redis for a specific period of time.
     * Used for creating `admin` and `user` sessions. Creates a `user` session token by default
     * @param options Options for creating the session
     */
    createSession(options: CreateSessionOptions): Promise<string>;
    /**
     * Creates a token that can be used for headless (i.e not triggered by a human user) inter-service calls by encrypting
     *  the service name and the id of the user whom the call is made for.
     * The token is not persisted instead a TTL of 1 minute is attached to the token after which the token becomes invalidated.
     * @param options Options for creating the headless token
     */
    createHeadlessToken(options: CreateHeadlessTokenOptions): Promise<string>;
    /**
     * Decrypts an encrypted token and returns the data contained within
     * @param token Encrypted token
     */
    decrypt<T = IDecoded>(token: string): Promise<T>;
    /**
     * Returns an Express middleware that guards requests to a particular endpoint using the token in the `Authorization` header against recognized `roles`.
     * @param roles The role(s) allowed to call the endpoint, defaults to `user`. Should be either `user` or `admin`
     * @param service The optional service(s) allowed to call the endpoint. `roles` should either contain or be `service` when this argument is provided.
     * If `service` is `"*"` all services can call the endpoint
     */
    guard(roles?: Role | Role[], service?: string | string[]): (req: Request, res: Response, next: NextFunction) => Promise<void>;
}