export declare function generateHmac(secret: string, data: string): string;
/** Generate HMAC for data string
 *  data param can be stringified object
 *  If apiKey is not provided, expects useProxyServer:true and a proxy server to be available to generate the hmac
 *  Expects proxyserver /oreid/hmac to host an endpoint to sign with the apiKey and return the hmac
 */
export declare function generateHmacWithApiKeyOrProxyServer(useProxyServer: boolean, apiKey: string, data: string): Promise<string>;
/** Generate HMAC for url string and append it to end or url e.g. http:/nnnnnn&hmac=xxx */
export declare function appendHmacToUrl(useProxyServer: boolean, apiKey: string, url: string): Promise<string>;