winston-winlog4

winston-winlog4 is a custom transport for Winston, designed to log messages to the Windows Event Log. It is a fork of winston-winlog2 and uses the node-eventlog library to write structured log data directly to the Windows Event Viewer. This transport is ideal for applications running on Windows where centralized, system-wide logging is beneficial.

Installation

Install via npm:

npm install winston-winlog4

Usage

To use winston-winlog4, import and add it to your Winston logger's transports.

import winston from 'winston';
import EventLogTransport from 'winston-winlog4';

const logger = winston.createLogger({
  transports: [
    new EventLogTransport({
      source: 'MyApplicationName', // Optional, defaults to 'node'
      level: 'info'                // Set the minimum level for this transport
    })
  ]
});

// Example logs
logger.info('Application started');
logger.warn('Potential issue detected');
logger.error('An error occurred');

This will log messages to the Windows Event Log under the specified source name, with levels info, warn, or error.

Options

The EventLogTransport class accepts the following options:

Option	Type	Description	Default
source	string	The source name shown in the Event Viewer	node
level	string	The minimum level of messages to log (info, warn, error)	info

Features

• Direct Windows Event Logging: Logs are sent to the Windows Event Log, accessible in the Windows Event Viewer.
• JSON Metadata Support: Includes metadata with each log, formatted as a JSON string, for easier log analysis.
• Supported Levels: Only logs at info, warn, or error levels are supported to match typical Windows Event Viewer log levels.
• Does Not Require Admin Privileges: The transport does not require admin privileges to write to the Event Log.
• Doesn't do anything on non-Windows platforms: The transport doesn't import native modules on non-Windows platforms.

Handling Metadata

Metadata is supported in the info parameter of the log function, where it is converted to a JSON string using flatted. If metadata cannot be parsed, it falls back gracefully with an error message. Any newlines in the log messages are removed for compatibility with the Event Viewer.

Development

To clone the repository and contribute:

git clone https://github.com/matteogheza/winston-winlog4
cd winston-winlog4
npm install

License

This module is licensed under the MIT License. See the LICENSE file for details.