Raw write data to bus

[buuuudzik]

Because there is no full support for all existing datatypes I think more useful would be open api by introducing some raw method to write data to bus with simple interface like: write(groupAddress, valueAsBuffer)

If it is about listening bus communication the library is good and probably I can say that it is reliable which not all knx libraries for node offer.

But writing is not very useful for me because of above issue. I think this library have very good communication reliability but should has minimum api, without datapoints. Datapoints and encoding/decoding buffered data should be in other lib and this part could change in the future but raw communication more probably no.

[buuuudzik]

I've found a way:

const knxSocket = new KNXTunnelSocket("1.0.16");

const write = (ga, value) => new Promise((resolve, reject) => {
    const buffer = encode(ga, value);
    const knxDataBuffer = new KNXDataBuffer(buffer);
    const srcAddress = KNXAddress.createFromString('7.0.2', KNXAddress.TYPE_GROUP);
    const destAddress = KNXAddress.createFromString(ga, KNXAddress.TYPE_GROUP);
    knxSocket._knxClient.sendWriteRequest(srcAddress, destAddress, knxDataBuffer, (err) => {
        if (err) {
            console.log({err});
            reject(err);
        } else {
            resolve();
        }
    });
});

[dufourgilles]

Thanks for your feedback. I will add a generic write function.

[buuuudzik]

If this is not a problem then please add also read and response. Then the telegram queue would be handled in one place.

Thank you for this library

[dufourgilles]

I pushed a new version with generic DataPoint. See the README for an example. Let me know if modifications are required.

[buuuudzik]

I will test it later, after work, but it looks very good.

What about read and response request?

I have a little question about library which could be in README in reliability context: How this library will react on disconnection of ip router? Is it try to reconnect after reconnecting or I must build knx tunnel object once again?

Unfortunately I cannot now test it by myself because I test connection remotely. But what is the idea?

Thank you very much for response and help. For me now this is the best and reliable app for KNX connection.

[buuuudzik]

I've tried and it not works. genericDatapoint still expect encode in its _type. Only works when I pass something like this:

const buffer = encode(ga, value);
        const knxDataBuffer = new KNXDataBuffer(buffer);
        const destAddress = KNXAddress.createFromString(ga, KNXAddress.TYPE_GROUP);
        const genericDatapoint = new DataPoints.DataPoint(destAddress);
        genericDatapoint._type = {
            encode: value => encode(ga, value),
            decode: buffer => decode(ga, buffer),
        };
        genericDatapoint.bind(knxClient);
        await genericDatapoint.write(knxDataBuffer);
        return true;

But the goal should to pass only ready data buffer from value.

[dufourgilles]

_type should not be required. If _type is null, we either crash if you pass something else than a KNXDataBuffer ... or we use the KNXDataBuffer without further encoding.

Same for read, if no _type, we just return the KNXDataBuffer.

[buuuudzik]

Unfortunately it is required as you see below in Datapoint.write method:

async write(val: string|number|DPT10Value|DPT3Value|Date|DPT18Value|KNXDataBuffer|null = null): Promise<void> {
        if (this._knxTunnelSocket == null) {
            throw new Error('Datapoint not binded');
        }
        if (this._type == null && !(val instanceof KNXDataBuffer)) {
            throw new Error('Datapoint type not specified. Expecting KNXDataBuffer value');
        }
        const value = val == null ? this._value : val;
        const buf =  this._type ? new KNXDataBuffer(this._type.encode(value), this) : <KNXDataBuffer>val;
        await this._knxTunnelSocket.writeAsync(this._ga, buf);
    }

Same with this line, it needs to pass this or other Datapoint interface: new KNXDataBuffer(this._type.encode(value), this)

[dufourgilles]

this._type is not required if the value passed to write is a KNXBuffer.

Tested at home. It works. See below the log where I print the generic DataPoint _type value.

gdufour@gdnet2:/mnt/raid/Node/test$ node t.js _sendSearchRequestMessage 192.168.1.2 null Connecting to 192.168.1.46 3671 Connected through channel id 42 Reading lamp status Lamp status: 0 Generic DP Write null ^C

                .then(() => {
                **console.log("Generic DP Write", genericDP._type);**
                const buf = Buffer.alloc(1);
                buf.writeUInt8(1, 0);
                const kbuf = new KNXDataBuffer(buf);
                return genericDP.write(kbuf);
         })