websockets rrto trep rdp-api refinitiv-realtime-optimised elektron-sdk refinitiv-realtime python authentication elektron connection api posting rics ADS c# fields mrn forex node-js cloud pricing token r refresh error-login batch rkd-api market-by-order streaming-prices chain-ric conflation log-in licensing documentation .net historical javascript websocket quote data java credentials time-stamp news DACS post Service key contributions delayed-feed disconnection domain aws date snapshot-pricing time-series eikon warrants ipa error-400 futures error page marketpsych app-key sample-code symbology messages batch-request sink-driven-source record-matching-api logging description typescript permissioning rfa eikon-data-api status ATS error-message sso ts1 caching streaming-data market-feed angular rcc-api parser document json CONTEX webscoket api response c economic-data support stream-id symbol-list encryption url port-number error-502 web entitlements stream-state race-condition synchronous condition-codes java-8 eap api-limits trade qos performance elektron-data-dictionary open-dacs tick-data dss-rest-api derivatives level-2 OMM exchange-codes exception FID market-holidays denied-by-src unix time