Struct LoopbackTransport 

pub struct LoopbackTransport { /* private fields */ }

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

A transport is created disconnected; connect registers it with the broker so it can publish and receive. Inbound messages are read with recv.

Examples

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

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

subscriber.subscribe("sensors/+/temperature").await?;
publisher.send("sensors/1/temperature", b"21.5").await?;

let message = subscriber.recv().await?.expect("a message");
assert_eq!(message.topic, "sensors/1/temperature");
assert_eq!(message.payload, b"21.5");

Implementations

impl LoopbackTransport

pub fn new(broker: LoopbackBroker) -> Self

Creates a disconnected transport bound to broker.

Arguments

• broker - the shared broker this transport publishes to and receives from.

Returns

A disconnected transport ready for connect.

pub fn is_connected(&self) -> bool

Reports whether the transport is connected to its broker.

Returns

true once connect has succeeded and before disconnect is called.

pub async fn recv(&mut self) -> Result<Option<Message>>

Awaits the next message from any subscribed topic.

Returns

Some(message) for the next message, or None once the broker and all other transports have been dropped.

Errors

Returns Error::Closed if the transport is not connected.

pub fn disconnect(&mut self)

Disconnects the transport from the broker.

Its registration is pruned from the broker on the next publish.

Trait Implementations

impl Transport for LoopbackTransport

async fn connect(&mut self) -> Result<()>

Establishes the connection to the broker, peer, or bus.

async fn send(&mut self, topic: &str, payload: &[u8]) -> Result<()>

Publishes a payload to a topic.

async fn subscribe(&mut self, topic: &str) -> Result<()>

Subscribes to a topic so that matching payloads are routed to this transport.