s3_client.rb

# frozen_string_literal: true

class S3Client
  def initialize(bucket_name:)
    @bucket_name = bucket_name
  end

  def download(key:, filepath: nil)
    return unless exist_key?(key)
    if filepath
      bucket.object(key).download_file(filepath)
    else
      bucket.object(key).get.body.read
    end
  end

  def upload(key:, filepath:)
    return if exist_key?(key)
    bucket.object(key).upload_file(filepath)
  end

  private

  def exist_key?(key)
    bucket.object(key).exists?
  end

  def bucket
    @bucket ||= begin
      s3 = Aws::S3::Resource.new
      s3.bucket(@bucket_name)
    end
  end
end