【ラズパイでもDocker！】Dockerコンテナ越しにシリアル通信を叩くNode.jsアプリの作成方法

            $ npm insall serialport
#OR
$ yarn add serialport
        

            const SerialPort = require('serialport');
const Readline = require('@serialport/parser-readline');

//👇ゲスト上のSerialデバイスに名前を合せる
const portName = '/dev/ttyUSB0';

//👇接続先(Arduino)のシリアルモデムを考慮
const sp = new SerialPort(portName, {
    baudRate: 9600,
    dataBits: 8,
    parity: 'none',
    stopBits: 1,
    flowControl: false,
});

//👇ポート開放時の初期化処理
sp.on('open', ()=> {
    console.log('Open Serialport');
});

//👇パーサクラスを指定
const parser = sp.pipe(new Readline());

//👇データ(Arduino > ラズパイ)の受信
parser.on('data', (inp_) => {
    try {
        console.log(`Received: ${inp_}`);
    } catch(e) {
        return;
    }
});
        

            FROM arm32v7/node:12-alpine3.11

RUN apk update && apk upgrade && apk add --no-cache \
    --virtual sp-deps make gcc g++ python alpine-sdk linux-headers udev

ENV NODE_ENV development
WORKDIR /usr/src/app

COPY package.json /usr/src/app/

RUN cd /usr/src/app && yarn install && yarn cache clean

RUN apk del sp-deps

COPY index.js /usr/src/app/
CMD ["node", "index.js"]
        

            {
    "name": "serial-dckr",
    "version": "0.0.1",
    "license": "MIT",
    "dependencies": {
        "serialport": "^9.0.0"
    }
}
        

            $ docker build -t serial-dckr:node12 .
        

            $ docker run -it \
    --rm \
    --device=/dev/ttyACM0:/dev/ttyUSB0 \
    --name piserial \
    serial-dckr:node12
#👇node index.jsのプロセスが走り出す
Open Serialport
Received: LED OFF
Received: LED ON
Received: LED OFF
Received: LED ON
#...省略
        

            $ docker stop piserial
        

            $ docker run --device=<ホスト上のデバイス名>[:コンテナ上のデバイス名][:権限タイプ] ...
        

            $ docker run --device=/dev/ttyACM0 ...
#👇と同じ
$ docker run --device=/dev/ttyACM0:/dev/ttyACM0 ...
        

            $ docker run --privileged -it <コンテナ名>