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