elasticsearch_url = ENV.fetch('ELASTICSEARCH_URL', 'http://localhost:9200')
elasticsearch     = Elasticsearch::Client.new(url: elasticsearch_url, trace: true)
importer          = Importer.new

importer.batch_handler = lambda do |actions|
  elasticsearch.bulk(body: actions)
end

importer.start
csv = CSV.new(File.open('data/books.csv', 'r'), headers: true)
csv.each do |row|
  importer << {
    index: {
      _index: 'books',
      _type: 'doc',
      data: row.to_hash
    }
  }
end

importer.finish