Message Flow
The message flow through the adapter is initiated by the start command.
The connector receives FIX data as a byte stream. FIX messages are preparsed into string objects. The QuickFIX API parses the strings into field maps, and those field maps are passed on to the Message Distributor.
The Message Distributor converts each field map into a number of records targeting a stream cluster. The records are now ready to be published to Event Stream Processor. However, they are not published immediately. Records are queued, then picked up by the Publisher object on separate threads, one thread for each record queue. You can configure the queue capacity. A larger queue is less likely to overflow in the event of a message burst. When the queue becomes three-quarters full, a warning is logged. Another warning is logged when the queue returns to three-quarters empty. If the queue is full, the adapter waits until room becomes available before placing the next record.
Records are published asynchronously. The adapter receives no feedback from Event Stream Processor.
If you are using the adapter with Event Stream Processor, in the event of a failover, the SDK interface switches to the spare Event Stream Processor instance without message loss.