Clone (import/export) an Elasticsearch index

clone_index.rb

index = args[:index] # If you're in a Rake task

# You'll have to write your own code for this part.
# It just creates an index for you, like so:
# es.indices.create(index: index, body: mappings_and_such)
ci = CreateIndex.new(index)
ci.create

es = Elasticsearch::Client.new
es_prod = Elasticsearch::Client.new(url: ENV['PROD_ELASTICSEARCH_URL'])

results = es_prod.search(
    index:  index,
    scroll: '5m',
    size:   1000,
    body:   { query: { match_all: {} } }
)

while results['hits']['hits'].present? do
  puts "Inserting #{results['hits']['hits'].size} documents..."

  es.bulk(
      index: index,
      body: results['hits']['hits'].map { |result| [ { create: { _id: result['_id'], _type: result['_type'] } }, result['_source'] ] }.flatten
  )

  results = es_prod.scroll(scroll_id: results['_scroll_id'], scroll: '5m')
end