LogLayer

LogLayer

Unifies Logging

A layer on top of Javascript logging libraries to provide a consistent logging experience.

What is LogLayer?
Quickstart
GitHub (MIT Licensed)
LogLayer

Structured Logging

Write logs with a fluid API that makes adding tags, metadata and errors simple.

Bring Your Own Logger

Use console logging when starting out, then switch to another logging provider later without changing your application code.

Extensible Plugin System

Transform, enrich, and filter logs with plugins that lets you customize every aspect of your logging pipeline.

Multi-logger Support

Fan out logs to multiple logging libraries and cloud providers such as DataDog and New Relic at the same time.

javascript
// Example using the Pino logging library with LogLayer
// You can also start out with a console logger and swap to another later!
import { LogLayer } from 'loglayer';
import { pino } from 'pino';
import { PinoTransport } from '@loglayer/transport-pino';
import { redactionPlugin } from '@loglayer/plugin-redaction';

const log = new LogLayer({
  // Multiple loggers can also be used at the same time. 
  transport: new PinoTransport({
    logger: pino()
  }),
  // Plugins modify log data before it's shipped to your logging library.
  plugins: [
    redactionPlugin({
      paths: ['password'],
      censor: '[REDACTED]',
    }),
  ],
})

log.withPrefix("[my-app]")
  .withMetadata({ some: 'data', password: 'my-pass' })
  .withError(new Error('test'))
  .info('my message')
json5
{
  "level": 30,
  "time": 1735857465669,
  "msg": "[my-app] my message",
  // The placement of these fields are also configurable!
  "password": "[REDACTED]",
  "some": "data",
  "err":{
    "type": "Error",
    "message": "test",
    "stack": "Error: test\n ..."
  }
}

Logging Libraries ​

  • AWS Lambda Powertools Logger - Logging for AWS Lambdas
  • Bunyan - JSON logging library for Node.js
  • Console - Simple console-based logging for development
  • Consola - Elegant console logger for Node.js and browser
  • Electron-log - Logging library for Electron applications
  • Log4js - Port of Log4j framework to Node.js
  • loglevel - Minimal lightweight logging for JavaScript
  • Pino - Very low overhead Node.js logger
  • Roarr - JSON logger for Node.js and browser
  • Signale - Highly configurable CLI logger
  • tslog - Powerful, fast and expressive logging for TypeScript and JavaScript
  • Tracer - Tracer logging library for Node.js
  • Winston - A logger for just about everything.

Cloud Providers ​