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