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