express-winston-2

0.0.2 verified Sat Apr 25 auth: no javascript

Logging middleware for Express.js using winston. Version 0.0.2 (latest). Provides request and error logging with whitelist support for request/response properties, custom log levels based on status code, and skip/ignore functionality. Differentiator: uses winston's flexible transport system and allows fine-grained control over log level via a callback function. Basic functionality, rarely updated.

Common errors

error Cannot find module 'express-winston-2' ↓

cause Package not installed or typo in module name.

fix

Run 'npm install express-winston-2' and check spelling in require().

error TypeError: expressWinston.logger is not a function ↓

cause Incorrect import or module load failure.

fix

Ensure required correctly: const expressWinston = require('express-winston-2');

error Error: Invalid winston transport ↓

cause Transport object is not an instance of winston.Transport.

fix

Use 'new winston.transports.Console()' or appropriate transport constructor.

error TypeError: Cannot read property 'statusCode' of undefined ↓

cause getLogLevel function expects statusCode argument but response object is passed.

fix

Change getLogLine to getLogLevel and accept (statusCode) instead of (res).

Warnings

gotcha Package is not ESM compatible; using import syntax will fail. ↓

fix Use require() instead of import.

gotcha The logger middleware must be placed after the router and before custom error handlers for proper error logging. ↓

fix Order middleware as: router, expressWinston.logger, expressWinston.errorLogger, error handlers.

deprecated The whitelist feature is marked as new in 0.2.x but may be removed in future versions. ↓

fix Check changelog before upgrading; consider alternatives like express-winston.

gotcha Setting winstonInstance ignores the transports option; only one should be used. ↓

fix Use either transports or winstonInstance, not both.

gotcha The getLogLevel function receives the response status code, not the response object. ↓

fix Define getLogLevel with parameter (statusCode) to return log level.

Install

npm install express-winston-2

yarn add express-winston-2

pnpm add express-winston-2

Imports

expressWinston

wrong

import expressWinston from 'express-winston-2';

correct

const expressWinston = require('express-winston-2');

Package does not support ESM. Must use require().

logger
wrong
```
expressWinston.Logger(options)
```
correct
```
expressWinston.logger(options)
```
logger is a method, not a constructor. Case-sensitive.

errorLogger

wrong

expressWinston.errorlogger(options)

correct

expressWinston.errorLogger(options)

errorLogger method name is camelCase.

Quickstart

Shows how to set up express-winston-2 middleware with console transport and custom message format.

const winston = require('winston');
const expressWinston = require('express-winston-2');
const express = require('express');
const app = express();

app.use(expressWinston.logger({
  transports: [
    new winston.transports.Console({ json: true, colorize: true })
  ],
  meta: true,
  msg: 'HTTP {{req.method}} {{req.url}}',
  expressFormat: true,
  colorStatus: true,
  ignoreRoute: function (req, res) { return false; }
}));

app.use(require('./my-router'));

const port = process.env.PORT || 3000;
app.listen(port, () => console.log('Server started'));