elektron refinitiv-realtime eta-api elektron-sdk rrt elektron-transport-api java rssl c++ rcc-api connection source-directory symbology trep batch log-in api fields c ssl reactor consumer rdm Service eikon rics ETA market-feed callback token status DACS ADS elektron-data-dictionary market-by-price non-interactive-provider linux rcc ipa snapshot-pricing sink-driven-source rdf sequence encoding stream-id error docker ADH service-name performance 64-bit multi-threading events mrn time-stamp conflation chain-ric stale enum service discovery OMM open-source equities elektron-direct-feed message commodities exchanges fanout contributions failover stress-test service-dictionary monitoring aws data-model build unsubscribe constituents api-limits service-id volume pricing dispatch trade quote documentation search tick-history-rest-api rfa load-balancing refresh-message compile subscription