SNSEvent to S3Event

sns2s3.js

/**
 * Extract an S3Event from the passed SNSEvent.
 * @param {import('aws-lambda').SNSEvent} snsEvent
 * @returns {import('aws-lambda').S3Event}
 */
function toS3Event (snsEvent) {
  const s3Event = { Records: [] }
  for (const snsRec of snsEvent.Records) {
    try {
      for (const s3Rec of JSON.parse(snsRec.Sns.Message).Records || []) {
        if (s3Rec.eventSource !== 'aws:s3') continue
        s3Event.Records.push(s3Rec)
      }
    } catch (err) {
      console.error(`failed to extract S3Event record from SNSEvent record: ${err.message}`)
    }
  }
  return s3Event
}