lambda-powertools-middleware-sample-logging

lambda-powertools-middleware-sample-logging

A Middy middleware that will enable debug logging for a configurable % of invocations. Defaults is 1%.

Main features:

• integrates with the @dazn/lambda-powertools-logger package to enable debug logging

• integrates with the @dazn/lambda-powertools-correlation-ids package to allow sampling decision to flow through correlation IDs - i.e. enable debug logging at the edge, and the entire call chain will respect that decision

• enables debug logging for some % (defaults to 1%) of invocations

• records an error log message with the invocation event as attribute when an invocation errors

Getting Started

Install from NPM: npm install @dazn/lambda-powertools-middleware-sample-logging

Alternatively, if you use the template @dazn/lambda-powertools-pattern-basic then this would be configured for you.

API

Accepts a configuration object of the following shape:

{
  sampleRate: double [between 0 and 1]
}

const middy = require('middy')
const sampleLogging = require('@dazn/lambda-powertools-middleware-sample-logging')

const handler = async (event, context) => {
  return 42
}

module.exports = middy(handler)
  .use(sampleLogging({ sampleRate: 0.01 }))
}

This middleware is often used alongside the @dazn/lambda-powertools-middleware-correlation-ids middleware to implement sample logging. It's recommended that you use the @dazn/lambda-powertools-pattern-basic which configures both to enable debug logging at 1% of invocations.