index.js

const middy = require('@middy/core')
const sampleLogging = require('@dazn/lambda-powertools-middleware-sample-logging')
const captureCorrelationIds = require('@dazn/lambda-powertools-middleware-correlation-ids')
const logTimeout = require('@dazn/lambda-powertools-middleware-log-timeout')
const supplementCsv = require('./supplement-csv')

const AWS_REGION = process.env.AWS_REGION || process.env.AWS_DEFAULT_REGION
const FUNCTION_NAME = process.env.AWS_LAMBDA_FUNCTION_NAME
const FUNCTION_VERSION = process.env.AWS_LAMBDA_FUNCTION_VERSION
const ENV = process.env.ENVIRONMENT || process.env.STAGE

if (process.env.DATADOG_PREFIX === undefined) {
  process.env.DATADOG_PREFIX = FUNCTION_NAME + '.'
}

process.env.DATADOG_TAGS = supplementCsv({
  existing: process.env.DATADOG_TAGS,
  additional: {
    awsRegion: AWS_REGION,
    functionName: FUNCTION_NAME,
    functionVersion: FUNCTION_VERSION,
    environment: ENV
  }
})

module.exports = f => {
  return middy(f)
    .use(captureCorrelationIds({
      sampleDebugLogRate: parseFloat(process.env.SAMPLE_DEBUG_LOG_RATE || '0.01')
    }))
    .use(sampleLogging({
      sampleRate: parseFloat(process.env.SAMPLE_DEBUG_LOG_RATE || '0.01')
    }))
    .use(logTimeout())
}