lsongdev / lsongdev/node-escpos

[BUG]: usb.on is not a function

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bug
Dominant language
TypeScript
Stars
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Description

### Description of the bug

```
\node_modules\escpos-usb\index.js:53
usb.on('detach', function(device){
^

TypeError: usb.on is not a function
at new USB (D:\GolandProjects\testprint\usb_printer_project\usb_printer_project_nodejs\node_modules\escpos-usb\index.js:53:7)
at Object. (D:\GolandProjects\testprint\usb_printer_project\usb_printer_project_nodejs\index.js:5:16)
at Module._compile (node:internal/modules/cjs/loader:1565:14)
at Object..js (node:internal/modules/cjs/loader:1708:10)
at Module.load (node:internal/modules/cjs/loader:1318:32)
at Function._load (node:internal/modules/cjs/loader:1128:12)
at TracingChannel.traceSync (node:diagnostics_channel:322:14)
at wrapModuleLoad (node:internal/modules/cjs/loader:219:24)
at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:170:5)
at node:internal/main/run_main_module:36:49

Node.js v22.12.0
```
```
"escpos": "^3.0.0-alpha.6",
"escpos-usb": "^3.0.0-alpha.4"
```

### Steps To Reproduce

直接使用示例
```
npm init -y
npm install escpos escpos-usb
node index.js
```

```
const escpos = require("escpos");
// install escpos-usb adapter module manually
escpos.USB = require("escpos-usb");
// Select the adapter based on your printer type
const device = new escpos.USB();
// const device = new escpos.Network('localhost');
// const device = new escpos.Serial('/dev/usb/lp0');

const options = { encoding: "GB18030" /* default */ };
// encoding is optional

const printer = new escpos.Printer(device, options);

device.open(function (error) {
printer
.font("a")
.align("ct")
.style("bu")
.size(1, 1)
.text("The quick brown fox jumps over the lazy dog")
.text("敏捷的棕色狐狸跳过懒狗")
.barcode("1234567", "EAN8")
.table(["One", "Two", "Three"])
.tableCustom(
[
{ text: "Left", align: "LEFT", width: 0.33, style: "B" },
{ text: "Center", align: "CENTER", width: 0.33 },
{ text: "Right", align: "RIGHT", width: 0.33 },
],
{ encoding: "cp857", size: [1, 1] } // Optional
)
.qrimage("https://github.com/song940/node-escpos", function (err) {
this.cut();
this.close();
});
});

```

### Additional Information

_No response_

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with the example entry point in index.js and inspect node_modules/escpos-usb/index.js at line 53, where usb.on is called. Reproduce the error with npm install followed by node index.js using Node.js 22. Done means the example no longer raises the TypeError when creating escpos.USB.

Written by the indexing model from the issue text.

Assessment

Tech stack
javascript, nodejs
Domain
embedded-iot
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
38/100

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