Crate pamoja_loopback 

An in-process loopback transport for hardware-free testing and examples.

LoopbackTransport implements the core Transport and Receive traits against a shared in-memory LoopbackBroker instead of a network, so examples, the simulators, and the cross-language conformance scenarios can exercise the full publish/subscribe path with no broker process and no hardware. Topic filters follow MQTT semantics, including the + single-level and # multi-level wildcards.

Clone one broker into every transport that should share a namespace: a publish on any transport is delivered to every transport whose subscriptions match.

Faulty decorates any transport to inject send failures, so degraded-link behavior such as store-and-forward retry can be tested deterministically.

Examples

A sensor and a gateway on one broker, with no network between them: the gateway subscribes to every node’s temperature, and a reading published by one node reaches it.

use pamoja_core::{Receive, Transport};
use pamoja_loopback::{LoopbackBroker, LoopbackTransport};

let broker = LoopbackBroker::new();
let mut gateway = LoopbackTransport::new(broker.clone());
let mut sensor = LoopbackTransport::new(broker);
gateway.connect().await?;
sensor.connect().await?;

gateway.subscribe("sensors/+/temperature").await?;
sensor.send("sensors/7/temperature", b"21.5").await?;

let reading = gateway.recv().await?.expect("the reading arrives");
assert_eq!(reading.topic, "sensors/7/temperature");
assert_eq!(reading.payload, b"21.5");

Structs

Faulty

Wraps a [Transport] and fails a configurable number of upcoming sends.

LoopbackBroker

A shared, in-process router for LoopbackTransports.

LoopbackTransport

An in-process transport that routes through a shared LoopbackBroker.

Message

A message that arrived on a subscribed topic.