LogTape Windows Event Log sink

Windows Event Log sink for LogTape. This package provides a Windows Event Log sink that sends log messages directly to the Windows Event Log system with cross-runtime support and optimal performance.

Features

Native Windows integration: Direct integration with Windows Event Log system
Cross-runtime: Works on Deno, Node.js, and Bun
High performance: Uses runtime-optimized FFI implementations
Structured logging: Preserves structured data in Event Log entries
Unicode support: Full support for international characters and emoji
Platform safety: Automatically restricts installation to Windows platforms
Zero dependencies: No external dependencies for Deno and Bun

Installation

This package is available on JSR and npm. You can install it for various JavaScript runtimes and package managers:

deno add jsr:@logtape/windows-eventlog  # for Deno
npm  add     @logtape/windows-eventlog  # for npm
pnpm add     @logtape/windows-eventlog  # for pnpm
yarn add     @logtape/windows-eventlog  # for Yarn
bun  add     @logtape/windows-eventlog  # for Bun

[!NOTE] This package is only available for Windows platforms. The package installation is restricted to Windows ("os": ["win32"]) to prevent accidental usage on other platforms.

Usage

The quickest way to get started is to use the getWindowsEventLogSink() function with your application source name:

import { configure } from "@logtape/logtape";
import { getWindowsEventLogSink } from "@logtape/windows-eventlog";

await configure({
  sinks: {
    eventlog: getWindowsEventLogSink({
      sourceName: "MyApplication",
    }),
  },
  loggers: [
    { category: [], sinks: ["eventlog"], lowestLevel: "info" },
  ],
});

You can also customize the sink behavior with additional options:

import { configure } from "@logtape/logtape";
import { getWindowsEventLogSink } from "@logtape/windows-eventlog";

await configure({
  sinks: {
    eventlog: getWindowsEventLogSink({
      sourceName: "MyApplication",
      eventIdMapping: {
        error: 1001,
        warning: 2001,
        info: 3001,
      },
    }),
  },
  loggers: [
    { category: [], sinks: ["eventlog"], lowestLevel: "info" },
  ],
});

[!NOTE] The Windows Event Log sink always writes to the Application log. This is the standard location for application events and does not require administrator privileges.

Runtime support

The Windows Event Log sink works across multiple JavaScript runtimes on Windows:

Deno: Uses Deno's native FFI for optimal performance
Node.js: Uses the koffi library for FFI bindings
Bun: Uses Bun's native FFI for maximum performance

Viewing logs

Once your application writes to the Windows Event Log, you can view the logs using:

Event Viewer (eventvwr.msc)
PowerShell: Get-WinEvent -FilterHashtable @{LogName='Application'; ProviderName='MyApplication'}
Command Prompt: wevtutil qe Application /f:text /q:"*[System[Provider[@Name='MyApplication']]]"

Docs

The docs of this package is available at https://logtape.org/manual/sinks#windows-event-log-sink. For the API references, see https://jsr.io/@logtape/windows-eventlog.