bytearray.go

s3Buffer, numBytes, err :=  DownloadS3File(event.S3Bucket, event.S3ObjectID, session)

header, err = GetHeader(s3Buffer)

var outBuffer []byte

if HeaderIndicatesConversionNeeded(header) {
  outBuffer, err = ConvertBuffer(s3Buffer, event.ObjectID)
} else {
  // outBuffer = s3Buffer or copy(outBuffer, s3Buffer) or ??
}

// use outBuffer...