Sample of how to provide resol vbus - data as Homie structure in a mqtt server

This is an example of how to read data from your resol device and transform the data to the Homie format.

This project uses the great library resol-vbus from Daniel Wippermann to read VBUS-information from the serialport.

What you need to adjust

in index.ts you need to provide information about your mqtt-server and serial port

export const mqttConfig: HomieMqttServerConfig = {
    brokerUrl: 'mqtt://myServer',
    username: 'myUsername',
    password: 'myPassword',
    homieBaseTopic: 'homie' // only change this if your home-automation software
                            // doesn't listen at the default base-topic
};

const path = '/dev/ttyUSB0';

in vbus-reader.ts you need to whitelist the fields you are interested in

const pumpSpeedRelay1 = 'Pump speed relay 1';
const temperatureSensor1 = 'Temperature sensor 1';
const temperatureSensor2 = 'Temperature sensor 2';
const temperatureSensor3 = 'Temperature sensor 3';
// most of the time we only need a few paketFields, so whitelist the desired ones
const whitelist = [
    pumpSpeedRelay1,
    temperatureSensor1,
    temperatureSensor2,
    temperatureSensor3
];

You also need to provide the Homie structure to which the vbus-data gets converted. You can find a sample in vbus-reader.ts#initHomieDevice

this.homieDevice = HomieDevice.create('vbus', 'Solar-Info', this.mqttConfig);
const kollektorNode = {
    homieInitialized: false,
    nodeId: 'kollektor',
    nodeName: 'Kollektor',
    properties: {
        temperatur: {
            type: 'float',
            value: undefined
        }
    }
} as DeviceNode;

this.homieDevice.addNodes(kollektorNode);

The last thing to do is to actually wire where the vbus information should be used:

this.vbusInfos$$
    .pipe(
        // Only emit info every 10seconds
        throttleTime(10000)
    )
    .subscribe(infos => {
        // use the vbus-value with name "Temperature sensor 1" for the 
        // property "temperatur" of the kollektorNode 
        this.updateIfPresent(infos, temperatureSensor1, kollektorNode, 'temperatur');
    });

To get all available fields for your device, take a look at logger.ts and change the log level to 'silly':

export const myLogger = winston.createLogger({
    level: 'silly', // <== change log level here
    format: combine(splat(), simple(), timestamp(), prettyJson),
    transports: [new winston.transports.Console({})],
});

After starting the application you should now see a bunch of JSON and hopefully find the right information.

To inspect the information I recommend writing it to a file and opening this file with your favorite editor:

npx ts-node src/index.ts > output.txt

Start

Setup (only once)

Install node from https://nodejs.org/de/download/

Tip: Use a version with an even number, because these have long term support

Open your preferred shell (cmd on Windows, bash, zsh) and run

npm install

Start

To start (and automatically transpile typescript to javascript)

npx ts-node src/index.ts

MQTT Homie structure

Openhab example

Please note that you need setup MQTT in openhab first.

There is a binding already available in the default installation: https://www.openhab.org/addons/bindings/mqtt/

After you've set MQTT up go to the openhab "Inbox" first and add the device.

Unfortunately the Plugin has an annoying bug, and will most likely tell you "did not receive mandatory topic XXX" after you open the newly created thing.

To overcome this, just restart this application and wait for the thing to get "green" :)