Printing Dari/Persian/Arabic with thermal printers in node.

thermal-printer-dari.js

/**
 * @typedef {object} printer
 * @property {string} name
 * @property {string} name_dari
 */

/**
 * @typedef {object} dbOrderItem
 * @property {number} order_id
 * @property {string} table_code
 * @property {string} name_dari
 * @property {number} count
 * @property {string} notes
 * @property {string} printer
 * @property {string} printer_dari
 * }
 */

/**
 * @typedef transformedOrder
 * @property {printer} printer
 * @property {string} printText
 */

/*
Sample config.js:

module.exports = {
    print: {
        pullIntervalInSeconds: 1,
        lineHeight: 35,
        width: 600,
        lineCharactersCount: 30,
        endLineCharacter: '\n'
    },
    db: {
        host: '127.0.0.1',
        database: 'xyz',
        user: 'root',
        password: ''
    },
    checks: {
        dumpIntervalInMinutes: 5
    }
};
*/

/*
date-time.js:

function now() {
    const date = new Date();
    return date.getFullYear() + '-' +
        (date.getMonth() + 1) + '-' +
        date.getDate() + ' ' +
        date.getHours() + ':' +
        date.getMinutes() + ':' +
        date.getSeconds();
}

module.exports = {
    now: now
};
*/
const importedThermalPrinter = require('node-thermal-printer').printer;
const thermalPrinterTypes = require('node-thermal-printer').types;
const printer = require('printer');
const config = require('../config');
const dateTime = require('./date-time');

/**
 * @param printerInfo {printer}
 * @param ordersText contains string
 */
async function order(printerInfo, ordersText) {

    const printingText =
        '\n******************\n' +
        'پرنتر: ' + printerInfo.name_dari +
        '\nزمان: ' + dateTime.now() + '\n' +
        '\n******************\n' + ordersText;
    const fetchedPrinter = printer.getPrinter(printerInfo.name);

    const createCanvas = require('canvas').createCanvas;
    const textLinesCount = printingText.split(config.print.endLineCharacter).length;

    canvas = createCanvas(
        config.print.width,
        config.print.lineHeight * textLinesCount
    );

    const ctx = canvas.getContext("2d");
    ctx.textAlign = "left";
    ctx.font = "30px bold";

    ctx.fillText(printingText, 0, 50);

    const thermalPrinter = new importedThermalPrinter({
        type: thermalPrinterTypes.EPSON,
    })

    await thermalPrinter.printImageBuffer(canvas.toBuffer());

    thermalPrinter.drawLine();
    thermalPrinter.partialCut();

    printer.printDirect({
        data: thermalPrinter.getBuffer(),
        printer: fetchedPrinter.name,
        type: "RAW",
        success: function (job_id) {
            console.log('OK :' + job_id);
        },
        error: function (error) {
            // TODO implement file logging
            console.error(error);
        }
    });
}

module.exports = {
    order: order
};