usb.on is not a function

[JuanDa237]

Node v18.15.0

"dependencies": {
"escpos": "^3.0.0-alpha.6",
"escpos-usb": "^3.0.0-alpha.4"
}

Code:

const escpos = require('escpos');
escpos.USB = require('escpos-usb');

const device = new escpos.USB(0x2BDF, 0x0280);
const printer = new escpos.Printer(device);

device.open(function (error) {
if (error) {
console.error('Error opening USB device:', error);
return;
}

printer
    .font('a')
    .align('ct')
    .style('bu')
    .size(1, 1)
    .text('Your Store Name')
    .text('----------------')
    .align('lt')
    .text('Item 1       $10.00')
    .text('Item 2        $7.50')
    .text('----------------')
    .align('rt')
    .text('Total:      $17.50')
    .cut()
    .close();

});

Error:
C:\Users\juan\Desktop\test-printer\node_modules\escpos-usb\index.js:52
usb.on('detach', function(device){
^

TypeError: usb.on is not a function
at new USB (C:\Users\x\Desktop\test-printer\node_modules\escpos-usb\index.js:52:7)
at Object. (C:\Users\x\Desktop\test-printer\index.js:5:16)
at Module._compile (node:internal/modules/cjs/loader:1254:14)
at Module._extensions..js (node:internal/modules/cjs/loader:1308:10)
at Module.load (node:internal/modules/cjs/loader:1117:32)
at Module._load (node:internal/modules/cjs/loader:958:12)
at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:81:12)
at node:internal/main/run_main_module:23:47

[SZZH]

maybe you can try, usb module version to 1

[SZZH]

maybe you can try, usb module version to 1

pnpm i usb@1.x

[giegiey]

npm install -S usb@1.8.0

[joshuayoes]

You can also run apply this patch-package patch

Add this to patch/escpos-usb+3.0.0-alpha.4.patch

diff --git a/node_modules/escpos-usb/index.js b/node_modules/escpos-usb/index.js
index 8c21546..7b3aa42 100644
--- a/node_modules/escpos-usb/index.js
+++ b/node_modules/escpos-usb/index.js
@@ -25,7 +25,7 @@ const IFACE_CLASS = {
 function USB(vid, pid){
 
   if (!usb) {
-    usb = require('usb');
+    usb = require('usb').usb;
   }
 
   EventEmitter.call(this);
@@ -67,7 +67,7 @@ function USB(vid, pid){
  */
 USB.findPrinter = function(){
   if (!usb) {
-    usb = require('usb');
+    usb = require('usb').usb
   }
   return usb.getDeviceList().filter(function(device){
     try{

Then run npx patch-package in your project.

[codewithshinde]

This worked for me !!

• go to node_modules/escpos-usb/index.js
• comment down the following lines

  // usb.on('detach', function(device){
  //   if(device == self.device) {
  //     self.emit('detach'    , device);
  //     self.emit('disconnect', device);
  //     self.device = null;
  //   }
  // });

[Cu4rach4]

Hi, im fixed this using the latest version of usb.
"usb": "^1.8.8"

then use Zadig driver.

[Zetjen]

#429 This was merged and fixed

[alexoxte]

#429 This was merged and fixed

I use latest package for escpos-usb, but the error persist I try use directy github repository and branch on my package.json, but cannot use them because typescript code isn't transpiled. any suggestion for it?

[Zetjen]

I see that the npm registry was updated 4 years ago and the same with GH registry, so first don't use the npm and GH package.

You can try to install from the repo directly. And then build it with tsc.

[Zetjen]

I'll try to push a GH action to automatically deploy and compile the package.

[alexoxte]

Maybe is necessary update version on package.json in ecspos-usb package

[dann95]

is this project open to pr for update usage of node-usb to latest versions? on version 3 it has broken the api on the listener .on();
forcing users to set resolutions to node-usb max at 1.9.2, node-usb is 1.9.2 is a bit old and may cause some problem in complations like electron etc. If this project is open for pr, i can do it

[clopezpro]

I use the version ^3.0.0-alpha.6 and "ESCPOS-USB": " ^3.0.0-alpha.4"
And I must even comment on the line

To work

[Zetjen]

@clopezpro I think that you can also do the following:

usb.usb.on('detach'....

so you don't lose the detach event.

Check this commit from a newer version: https://github.com/lsongdev/node-escpos/pull/429/files