Print only work the first time and I need to restart the bluetooth to print again.

[MarwenBenTalebAli]

I want to create a REST service with Node.js using Express that prints tickets to ESC/POS bluetooth printer.

The actual result my service print only the first time and I need to restart the bluetooth to print again.

I tried update my service to only look for the printer and return it but it only works a couple of times. I received this error in the console:

(node:16608) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 error listeners added to [Device]. Use emitter.setMaxListeners() to increase limit (Use node --trace-warnings ... to show where the warning was created)

The expected result print data multiple times

Here is my printerService.js :

const { Printer } = require("escpos");
const Bluetooth = require("escpos-bluetooth");

const foundPrinter = async (name, address, channel, printData) => {
  const PRINTER_NAME = name;
  const PRINTER_ADDRESS = address;
  const PRINTER_CHANNEL = channel;
  const preferredPrinterAddress = "(" + PRINTER_ADDRESS + ")" + PRINTER_NAME;
  const availablePrinters = await Bluetooth.findPrinters();
  console.log("availablePrinters", availablePrinters);
  const btPrinter =
    availablePrinters && availablePrinters.length > 0
      ? availablePrinters.filter(
          (p) =>
            p &&
            p.name === PRINTER_NAME &&
            p.address === preferredPrinterAddress
        )[0]
      : false;

  console.log("btPrinter", btPrinter);
  return new Promise((resolve, reject) => {
    if (btPrinter) {
      if (!printData) {
        resolve({ printer: btPrinter });
      } else {
        const device = new Bluetooth(PRINTER_ADDRESS, PRINTER_CHANNEL);
        const printer = new Printer(device);
        device.open(function (deviceError) {
          if (!deviceError) {
            printer
              .font("a")
              .align("ct")
              .style("bu")
              .size(1, 1)
              .text("Text1")
              .text("Text2")
              .barcode("1234567", "EAN8")
              .qrimage("qrImage", function (qrImageError) {
                if (!qrImageError) {
                  this.cut();
                  this.close();
                } else {
                  reject({
                    name: qrImageError.name,
                    message: qrImageError.message,
                  });
                }
              });
            resolve({ printer: btPrinter });
          } else {
            reject({ name: deviceError.name, message: deviceError.message });
          }
        });
      }
    } else {
      reject({
        errorType: "ERROR_PRINTER_NOT_FOUND",
        errorName: "PRINTER_NOT_FOUND",
        message: "printer not found",
        fullMessage:
          "printer not found, availablePrinters: " +
          availablePrinters.toString(),
      });
    }
  });
};

[mhaluphet129]

Hello @MarwenBenTalebAli how did you install escpos-bluetooth btw ?