serverless-finch/lib/bucket-utils.js

Deploy your serverless static website to AWS S3.

'use strict';

/**
 * Checks if an S3 bucket exists
 * @param {Object} aws - AWS class
 * @param {string} bucketName - Name of bucket to look for
 *
 * @returns {Promise<boolean>}
 */
function bucketExists(aws, bucketName) {
  return aws.request('S3', 'listBuckets', {}).then(resp => {
    let exists = false;
    resp.Buckets.forEach(bucket => {
      if (bucket.Name === bucketName) {
        exists = true;
      }
    });
    return exists;
  });
}

/**
 * Get a list of all objects in an S3 bucket
 * @param {Object} aws - AWS class
 * @param {string} bucketName - Name of bucket to scan
 */
function listObjectsInBucket(aws, bucketName) {
  const params = {
    Bucket: bucketName
  };
  return aws.request('S3', 'listObjectsV2', params);
}

/**
 * Deletes an S3 bucket
 * @param {Object} aws - AWS class
 * @param {string} bucketName - Name of bucket to be deleted
 */
function deleteBucket(aws, bucketName) {
  const params = {
    Bucket: bucketName
  };
  return aws.request('S3', 'deleteBucket', params);
}

/**
 * Deletes all objects in an S3 bucket
 * @param {Object} aws - AWS class
 * @param {string} bucketName - Name of bucket to be deleted
 *
 * @returns {Promise<boolean>} Whether all objects in the bucket were removed
 * (will be `false` if `keyPrefix` is provided and objects exist outside that prefix)
 */
function emptyBucket(aws, bucketName, keyPrefix) {
  return listObjectsInBucket(aws, bucketName).then(resp => {
    const contents = resp.Contents;
    let testPrefix = false,
      prefixRegexp;
    if (!contents[0]) {
      return Promise.resolve();
    } else {
      if (keyPrefix) {
        testPrefix = true;
        prefixRegexp = new RegExp('^' + keyPrefix);
      }
      const objectsToDelete = contents
        .map(function (content) {
          return { Key: content.Key };
        })
        .filter(content => !testPrefix || prefixRegexp.test(content.Key));

      const willEmptyBucket = objectsToDelete.length === contents.length;

      if (objectsToDelete.length === 0) {
        return Promise.resolve(willEmptyBucket);
      }

      const params = {
        Bucket: bucketName,
        Delete: { Objects: objectsToDelete }
      };

      return aws.request('S3', 'deleteObjects', params).then(() => willEmptyBucket);
    }
  });
}

/**
 * Creates S3 bucket with the given name
 * @param {Object} aws - AWS class
 * @param {string} bucketName - Name of bucket to be created
 */
function createBucket(aws, bucketName) {
  const params = {
    Bucket: bucketName
  };

  return aws.request('S3', 'createBucket', params).then(() => {
    return aws.request('S3', 'deletePublicAccessBlock', {
      Bucket: bucketName
    });
  });
}

module.exports = {
  bucketExists,
  createBucket,
  deleteBucket,
  emptyBucket,
  listObjectsInBucket
};