import { CanActivate, ExecutionContext } from "@nestjs/common";
/**
 * Guard that only allows access to a [Controller](https://docs.nestjs.com/controllers)
 * if there is an authenticated principal.
 *
 * It is recommended to use this in conjunction with the {@link BearerAuthenticationMiddleware}
 * and {@link CookieAuthenticationMiddleware} which set req.principal when there is an
 * authenticated session.
 *
 * @example API usage (returns 401 JSON)
 * ```typescript
 * @UseGuards(Authenticated)
 * @Get("me")
 * public me() {}
 * ```
 *
 * @example Server-rendered usage (redirects to login page)
 * ```typescript
 * @UseGuards(new Authenticated("/auth/magic-link"))
 * @Get("dashboard")
 * public dashboard() {}
 * ```
 */
export declare class Authenticated implements CanActivate {
    private readonly redirectUrl?;
    /**
     * @param redirectUrl - Optional URL to redirect unauthenticated users to.
     *   When provided, throws {@link UnauthorizedRedirectException} instead of a plain
     *   {@link UnauthorizedException}. The exception is still a 401 but carries redirect
     *   metadata via `getRedirect()` that an exception filter may use to issue an HTTP
     *   redirect for browser-based requests.
     */
    constructor(redirectUrl?: string | undefined);
    /**
     * If req.principal is truthy will return true so that request handling can be
     * passed onto the relevant [Controller](https://docs.nestjs.com/controllers)
     * method, otherwise throws an UnauthorizedException.
     *
     * @param { ExecutionContext } context - Context providing access to the underlying request.
     *
     * @returns { true } - If req.principal is set.
     *
     * @throws { UnauthorizedException } - If req.principal is not set.
     * @throws { UnauthorizedRedirectException } - If req.principal is not set and a redirect URL was provided.
     */
    canActivate(context: ExecutionContext): boolean;
}