rkd-api rkd data api query-string fundamentals news rics historical quote python token fields json c# search websockets symbology soap-api http php java proxy throttling bonds financial-statements .net street-events error rest-api xml fiddler authentication time-series perl commodities ssl document trep derivatives pe-code Service web exchange-holidays error-403 economic-data kotlin timeseries time-stamp performance r FTP etf request timestamp feeds api-limits pricing disconnection isin upgrading javadoc forex wsdl response key volatility transcript error-400 helpdesk swagger error-message connection-error news-filter postman documentation trade streaming-prices load-balancing bulk-download Download sectors equities pandas fundamental-data