The Event Store transport implements a message queuing mechanism on top of the Event Store stream database.
The Event Store transport does not rely on the projections functionality for routing messages. Instead, it maintains a routing topology data structure inside the database in a dedicated event stream
nsb-exchanges. The structure is a simplified version of AMQP 0.9.1 routing topology.
When a message is addressed to a given exchange
E it is copied to all exchanges (similar to AMQP
fanout exchange) and to all queues bound to that exchange. In the example above a message sent to the
ExchangeB would go to the
Queue1, and a message sent to the
ExchangeA would go to both the
Event Store transport supports Receive Only transaction mode. Refer to Transport Transactions for a detailed explanation of the supported transaction handling modes and available configuration options.