import { Request, Response, Middleware, HttpHeaderLiteral } from "./";
export declare type Portal<Request, Response> = (request: Request) => Promise<Response>;
/**
 * Read all response headers from the given XHR instance into a standard
 * object literal.
 */
export declare function getAllHeaders(xhr: XMLHttpRequest): HttpHeaderLiteral;
/**
 * Sends the request to the server.  This is used by createPortal() after
 * all middleware has been applied.
 */
export declare function send(request: Request): Promise<Response>;
/**
 * Creates and returns a new "portal" instance for creating HTTP
 * requests.  Each request and response is passed through the
 * given middleware.
 */
export declare function createPortal(...middleware: Middleware[]): <Req extends Request<any> = Request<any>, Res extends Response<any> = Response<any>>(request: Req) => Promise<Res>;