@embedded32/bridge

Route selected CAN/J1939 traffic to UDP, TCP, or MQTT using @embedded32/ethernet transports - gateway pattern for connected-vehicle labs.

Installation

npm install @embedded32/bridge @embedded32/ethernet @embedded32/can @embedded32/j1939 @embedded32/core

Minimum runnable example

Conceptual wiring (see package examples/ and supervisor config for full setup):

import { CanMqttBridge } from '@embedded32/bridge';
import { MQTTClient } from '@embedded32/ethernet';
import { CANInterface, MockCANDriver } from '@embedded32/can';

const can = new CANInterface(new MockCANDriver());
const mqtt = new MQTTClient({ broker: 'mqtt://localhost:1883' });

const bridge = new CanMqttBridge({
  canBus: can,
  mqtt,
  topicPrefix: 'classroom/bus1',
});

await bridge.start();

Requires a local MQTT broker for live forwarding.

Public API overview

Export	Role
`CanEthernetBridge`	CAN ↔ UDP/TCP forwarding with filters
`CanMqttBridge`	CAN ↔ MQTT topic mapping
`RuleEngine`	Priority rules, PGN whitelist/blacklist, rate limits
`BridgeRule`, `RoutingRule`	Configuration types

Runtime requirements

Node.js 18+
ESM package
@embedded32/ethernet for transports

Hardware requirements

None when using MockCANDriver. Production gateways typically use Linux SocketCAN plus network access to MQTT/UDP peers.

Browser compatibility

Node.js only. MQTT consumers may be browser apps, but this package runs on the gateway host.

Common errors

Error	Fix
MQTT connection refused	Start broker (`mosquitto`) or fix broker URL
No forwarded messages	Check PGN whitelist and `RuleEngine` default action
Wrong import path	Use `@embedded32/bridge`, not legacy unscoped name

@embedded32/ethernet - UDP, TCP, MQTT clients
@embedded32/j1939 - PGN-aware filtering
@embedded32/cli - load bridge via supervisor config

Version compatibility

@embedded32/bridge@1.0.0 (ESM) must pair with @embedded32/j1939@1.0.0 and @embedded32/ethernet@1.0.0.