Configuration

The core is a codec, so there’s almost nothing to configure — the “wiring” is your own broker client plus a couple of optional behaviours.

Envelope options

Make accepts functional options. Set the queue name (written to meta.queue) and continue an inbound trace across a hop:

env, _ := babelqueue.Make(
    "urn:babel:orders:created",
    map[string]any{"order_id": 1042},
    babelqueue.WithQueue("orders"),
    babelqueue.WithTraceID(inbound.TraceID), // omit to mint a fresh trace_id
)

Dead-letter

On failure, wrap the envelope in an additive dead_letter block and publish the copy to your dead-letter queue (e.g. orders.dlq):

dl := babelqueue.Annotate(env, "failed", "orders", 3, err)
body, _ := dl.Encode()
// publish body to the "orders.dlq" queue with your broker client

Annotate returns a copy — the original envelope is preserved unchanged inside the dead-lettered message, so any-language consumer can still read it.

Unknown-URN strategy

For adapters routing inbound messages, the strategy constants StrategyFail, StrategyDelete, StrategyRelease and StrategyDeadLetter describe what to do with a URN you don’t handle.

Next: Producing messages.