@middy/sqs-partial-batch-failure/index.js

SQS partial batch failure middleware for the middy framework

const defaults = {
  logger: console.error
}

const sqsPartialBatchFailureMiddleware = (opts = {}) => {
  const { logger } = { ...defaults, ...opts }

  const sqsPartialBatchFailureMiddlewareAfter = async (request) => {
    const {
      event: { Records },
      response
    } = request

    // https://docs.aws.amazon.com/lambda/latest/dg/with-sqs.html
    // Required: include the value `ReportBatchItemFailures` in the `FunctionResponseTypes` list
    const batchItemFailures = []
    if (Array.isArray(Records)) {
      for (const [idx, record] of Object.entries(Records)) {
        const { status, reason } = response[idx]
        if (status === 'fulfilled') continue
        batchItemFailures.push({ itemIdentifier: record.messageId })
        if (typeof logger === 'function') {
          logger(reason, record)
        }
      }
    }

    request.response = { batchItemFailures }
  }

  const sqsPartialBatchFailureMiddlewareOnError = async (request) => {
    if (request.response !== undefined) return

    // Force all to be sent to DLQ
    // const recordPromises = request.event.Records.map(async (record, index) => {
    //   throw request.error
    // })
    request.response = new Array(request.event.Records?.length).fill({
      status: 'rejected',
      reason: request.error
    })

    await sqsPartialBatchFailureMiddlewareAfter(request)
  }

  return {
    after: sqsPartialBatchFailureMiddlewareAfter,
    onError: sqsPartialBatchFailureMiddlewareOnError
  }
}

export default sqsPartialBatchFailureMiddleware