s3.js

'use strict';
var rfr = require('rfr');
var logger = rfr('util/logger');
var config = rfr('config');
var AWS = config.AWS;
var fs = require('fs');
var cf = rfr('/util/cloudFormation');

function uploadLambdaZipToS3() {
  return cf.getStackOutputs().then((cfOutputs) => {
    return {
      Bucket: cfOutputs.LambdaBucket,
      Key: config.getLambdaZipName(),
      Body: fs.createReadStream(config.getLambdaZipPath())
    };
  }).then((params) => {
    return putS3Object(params);
  });
}

function putS3Object(params) {
  return new Promise((resolve, reject) => {
    var s3obj = new AWS.S3({params: params});
    s3obj.upload({Body: params.Body}, function(err, data) {
      if (err) {
        reject(err);
        return;
      }
      logger.info('Successfully uploaded Lambda code to ' + params.Key);
      logger.info('Uploaded Lambda zip as s3://' + params.Bucket + '/' + params.Key);
      resolve(data);
    });
  });
}

function emptyBucket(bucketName) {
  return new Promise((resolve, reject) => {
    listObjects(bucketName).then((objectKeys) => {
      deleteObjects(bucketName, objectKeys).then((result) => {
        resolve(result);
      })
    }).catch((err) => {
      logger.error(err);
      reject(err);
    })
  })
}

function listObjects(bucketName) {
  return new Promise((resolve, reject) => {
    var objectKeys = [];
    var s3 = new AWS.S3();
    let params = {
      Bucket: bucketName
    };
    s3.listObjectsV2(params, function(err, data) {
      if (err) {
        logger.error(err);
        reject(err);
      }
      let objects = [];
      if (data && data.Contents) {
        objects = data.Contents;
      }
      for (let i = 0; i < objects.length; i++) {
        objectKeys.push(
          {
            Key: objects[i].Key
          }
        );
      }
      resolve(objectKeys);
    });
  });
}

function deleteObjects(bucketName, objectKeys) {
  return new Promise((resolve, reject) => {
    var s3 = new AWS.S3();
    if (objectKeys.length === 0) {
      // Bucket is already empty. There are no objects to delete
      resolve();
      return;
    }
    let params = {
      Bucket: bucketName,
      Delete: {
        Objects: objectKeys
      }
    };
    s3.deleteObjects(params, function (err, data) {
      if (err) {
        logger.error(err);
        reject(err);
        return;
      }
      resolve(data);
    })
  });
}

module.exports = {
  uploadLambdaZipToS3,
  emptyBucket
};