Uncaught TypeError: winston__WEBPACK_IMPORTED_MODULE_0__.format.errors is not a function

[bruceauyeung]

Please tell us about your environment:

I am using winston in an Electron application, based on VueJS framework, typescript class style

• winston version?
  • [ ] winston@2
  • [x] winston@3 winston@3.2.1
• node -v outputs: v12.4.0
• Operating System? (Windows, macOS, or Linux) CentOS 7
• Language? (all | TypeScript X.X | ES6/7 | ES5 | Dart) TypeScript 3.5.3

  What is the problem?

  when running, there is an error: logger.ts:9 Uncaught TypeError: winston__WEBPACK_IMPORTED_MODULE_0__.format.errors is not a function

my code:

import { createLogger, format, transports } from 'winston';

const logger = createLogger({
    level: 'info',
    format: format.combine(
        format.timestamp({
            format: 'YYYY-MM-DD HH-mm-ss'
        }),
        format.errors({ stack: true }),
        format.splat(),
        format.json(),
    ),
    defaultMeta: { service: 'my-service-name' },
    transports: [
        new transports.File({ filename: 'test-file-log-err.log', level: 'error' }),
        new transports.File({ filename: 'test-file-log-all.log' })
    ]
});

1. in vscode, when i type in format.err, vscode will suggest me errors, auto-completion looks good.
2. typescript compilation has no error.
3. but when i running this app, there is an error thrown out:

   logger.ts:9 Uncaught TypeError: winston__WEBPACK_IMPORTED_MODULE_0__.format.errors is not a function
   at Module../src/logger.ts (logger.ts:9)
   at __webpack_require__ (bootstrap:790)
   at fn (bootstrap:150)
   at Module../node_modules/cache-loader/dist/cjs.js?!./node_modules/babel-loader/lib/index.js!./node_modules/ts-loader/index.js?!./node_modules/cache-loader/dist/cjs.js?!./node_modules/vue-loader/lib/index.js?!./src/components/HelloWorld.vue?vue&type=script&lang=ts& (app.js:1030)
   at __webpack_require__ (bootstrap:790)
   at fn (bootstrap:150)
   at Module../src/components/HelloWorld.vue?vue&type=script&lang=ts& (HelloWorld.vue?5a2d:1)
   at __webpack_require__ (bootstrap:790)
   at fn (bootstrap:150)
   at Module../src/components/HelloWorld.vue (HelloWorld.vue?f177:1)

   What do you expect to happen instead?

   there shouldn't be an error related to errors function

[rhyek]

I think this is related to webpack and your project's configuration. I tested this in a newly created create react app project and I get the same issue. In the same project, if I run node -e "const { format } = require('winston'); console.log(format.errors);" I can see that the function does indeed exist. When running the react app, I get the error in the browser's console.

[rhyek]

Related: https://github.com/winstonjs/logform/issues/97 So not related to webpack. It's just the errors formatter is not being exposed to the browser by logform.

[bruceauyeung]

@rhyek today i tried to reproduce this bug, and like you said, format.errors function is not available in electron renderer process even when nodeIntegration is true