Input and output logger middleware for the middy framework

Usage no npm install needed!

<script type="module">
  import middyInputOutputLogger from 'https://cdn.skypack.dev/@middy/input-output-logger';


Middy input-output-logger middleware

Middy logo

Input output logger middleware for the middy framework, the stylish Node.js middleware engine for AWS Lambda

Logs the incoming request (input) and the response (output).

By default, the logging operate by using the console.log function. You can pass as a parameter a custom logger with additional logic if you need. It can be useful if you want to process the log by doing a http call or anything else.


To install this middleware you can use NPM:

npm install --save @middy/input-output-logger


  • logger function (default console.log): logging function that accepts an object
  • awsContext boolean (default false): Include AWS Lambda context object to the logger
  • omitPaths string[] (default []): property accepts an array of paths that will be used to remove particular fields import the logged objects. This could serve as a simple way to redact sensitive data from logs (default []).

Sample usage

import middy from '@middy/core'
import inputOutputLogger from '@middy/input-output-logger'

const handler = middy((event, context) => {
  const response = {
    statusCode: 200,
    headers: {},
    body: JSON.stringify({ message: 'hello world' })
  return response

import middy from '@middy/core'
import inputOutputLogger from '@middy/input-output-logger'
import pino from 'pino'
const logger = pino()

const handler = middy((event, context) => {
  // ...
  return response

    logger: (request) => {
      const child = logger.child(request.context)
      child.info(request.event ?? request.response)
    awsContext: true

Middy documentation and examples

For more documentation and examples, refers to the main Middy monorepo on GitHub or Middy official website.


Everyone is very welcome to contribute to this repository. Feel free to raise issues or to submit Pull Requests.


Licensed under MIT License. Copyright (c) 2017-2021 Luciano Mammino, will Farrell, and the Middy team.

FOSSA Status