@aws-lambda-powertools/logger

What is @aws-lambda-powertools/logger?

@aws-lambda-powertools/logger is a structured logging utility designed for AWS Lambda functions. It simplifies the process of creating consistent and meaningful logs, which can be crucial for debugging and monitoring serverless applications.

What are @aws-lambda-powertools/logger's main functionalities?

Basic Logging

This feature allows you to log basic information. The logger.info method is used to log informational messages.

const { Logger } = require('@aws-lambda-powertools/logger');
const logger = new Logger();

exports.handler = async (event) => {
  logger.info('This is an info log');
  return { statusCode: 200, body: 'Hello World' };
};

Structured Logging

Structured logging allows you to add context to your logs, making them more useful for debugging and monitoring. You can add persistent attributes that will be included in every log entry.

const { Logger } = require('@aws-lambda-powertools/logger');
const logger = new Logger({
  persistentLogAttributes: {
    service: 'my-service',
    environment: 'production'
  }
});

exports.handler = async (event) => {
  logger.info('This is a structured log', { userId: '12345' });
  return { statusCode: 200, body: 'Hello World' };
};

Error Logging

This feature allows you to log errors with additional context. The logger.error method is used to log error messages.

const { Logger } = require('@aws-lambda-powertools/logger');
const logger = new Logger();

exports.handler = async (event) => {
  try {
    throw new Error('Something went wrong');
  } catch (error) {
    logger.error('An error occurred', { error });
  }
  return { statusCode: 500, body: 'Internal Server Error' };
};

Other packages similar to @aws-lambda-powertools/logger

winston

Winston is a versatile logging library for Node.js that supports multiple transports (e.g., console, file, HTTP). It offers more flexibility and customization options compared to @aws-lambda-powertools/logger but requires more setup.

bunyan

Bunyan is another structured logging library for Node.js. It provides a JSON-based logging format and includes features like log levels and serializers. It is similar to @aws-lambda-powertools/logger in terms of structured logging but is more general-purpose.

pino

Pino is a fast JSON logger for Node.js applications. It is designed for high performance and low overhead. While it offers similar structured logging capabilities, it is more focused on performance compared to @aws-lambda-powertools/logger.

README

AWS Lambda Powertools TypeScript

⚠️ WARNING: Do not use this library in production ⚠️
AWS Lambda Powertools for TypeScript is currently released as a beta developer preview and is intended strictly for feedback purposes only. This version is not stable, and significant breaking changes might incur as part of the upcoming production-ready release.

A suite of TypeScript utilities for AWS Lambda functions to ease adopting best practices such as tracing, structured logging, custom metrics, and more. (AWS Lambda Powertools Python and Java are also available).

📜 Documentation | NPM | Roadmap | Examples

An AWS Developer Acceleration (DevAx) initiative by Specialist Solution Architects | [e-mail]

Features

• Tracer - Utilities to trace Lambda function handlers, and both synchronous and asynchronous functions
• Logger - Structured logging made easier, and a middleware to enrich log items with key details of the Lambda context
• Metrics - Custom Metrics created asynchronously via CloudWatch Embedded Metric Format (EMF)

Getting started

Find the complete project's documentation here.

Installation

The AWS Lambda Powertools TypeScript utilities follow a modular approach, similar to the official AWS SDK v3 for JavaScript.
Each TypeScript utility is installed as standalone NPM package.

👉 Installation guide for the Tracer utility

👉 Installation guide for the Logger utility

👉 Installation guide for the Metrics utility

Examples

• CDK
• Tracer
• Logger
• Metrics

Credits

• Credits for the Lambda Powertools idea go to DAZN and their DAZN Lambda Powertools.

Connect

• AWS Developers Slack: #lambda-powertools** - Invite, if you don't have an account
• Email: [e-mail]

License

This library is licensed under the MIT-0 License. See the LICENSE file.