Remove old indices on ElasticSearch

remove_old_indices.rb

#!/usr/bin/env ruby

require 'pp'
require 'net/http'
require 'date'
require 'json'


endpoint    = "http://<HOST>:<PORT>/" 
expire_days = 7


def request(method, uri)
  begin
    uri           = URI.parse(uri)
    request       = Net::HTTP.new(uri.host, uri.port)
    response      = request.__send__(method.downcase, uri.path)
    response_json = JSON.parse(response.body)
  rescue => ex
    warn "[Error] #{ex.message}"
    warn "[Error] #{ex.backtrace}"
    return false
  end
  response_json
end


status = request("GET", endpoint + "_status")
if status["indices"].nil?
  warn "[Error] Get Index list failed."
  exit
end

status["indices"].each do |index_name, data|
  index_prefix, year, month, day = index_name.scan(/^([\w\.\_]+)-(\d{4})\.([0-1][0-9])\.?([0-3][0-9])?/).flatten

  if year.nil? || month.nil?
    puts "[Info] target index: #{index_name} is unexpected index name."
    next
  end

  day = "-1" if day.nil?
  
  elapsed_days = (Date.today - Date.new(year.to_i, month.to_i, day.to_i)).to_i

  if expire_days - elapsed_days > 0
    puts "[Info] target index: #{index_name} is skipped."
    next 
  end

  unless request("DELETE", endpoint + index_name)
    warn "[Error] target index: #{index_name} delete failed."
    next 
  end

  puts "[Info] target index: #{index_name} is deleted."
end