Refactor node.js snippet

refactor.js

function prepareDoc(item) {

  var obj = {
    id: item.id,
    hash: item.hash,
    title: item.title,
    account_id: item.AccountId,
    text: item.body,
    createdAt: item.created_at,
    updatedAt: item.updated_at,
    attachments: prepareAttachments(item.Images),
  };

  return obj;
}

function prepareAttachments(attachments) {
  var base64AttachmentArray = [];

  for(var i=0;i < attachments.length;i++) {

    var params = { Bucket: process.env.UPLOAD_BUCKET, Key: attachments[i].key };
    s3.getObject(params, function(err, data) {

      if (err) {
        logger.error(err);
        return err;
      } else {
        var objectData = {
            data: data.Body.toString('base64')
        };
        base64AttachmentArray.push(objectData);
      }
    });
  }
  return base64AttachmentArray;
}