RabbitMQ transport

This optional transport serves the self-managed reliable messaging provider. It does not own an Inbox or Outbox. Publishing uses persistent messages, a stable AMQP MessageId, publisher confirmations with tracking, and mandatory=true. A return is a permanent routing failure; a nack or disconnected confirmation remains a failed/unknown publication, never success.

The JSON body is the event payload. ms-contract-name, ms-contract-version, and ms-occurred-at identify its registered contract and exact UTC occurrence time. W3C tracing headers and correlation identifiers are preserved. Message limits are measured in UTF-8 bytes.

The host supplies RabbitMqOptions.ConnectionString; the library contains no broker credentials. Declare the expected durable topology using the explicit provisioning entry point before starting an application. Publishing checks that the exchange exists and requires a route, but mandatory publication alone cannot prove every intended subscription binding exists.

Source copies require this project, Messaging.Abstractions, RabbitMQ.Client, and the host’s Microsoft.Extensions dependencies. Unit tests use interface substitutes; actual broker recovery belongs to the separate integration test suite.