China region

china_region.rb

# rails g model ChinaRegion name parent_id lng lat

class AddChinaRegionData < ActiveRecord::Migration[6.0]
  def up
    # https://github.com/pfinal/city
    ChinaRegion.destroy_all
    ActiveRecord::Base.connection.reset_pk_sequence!(ChinaRegion.table_name)
    data = []
    File.open(Rails.root.join('db', 'data', 'region.txt')).each do |line|
      next unless /\((.*)\).*/ =~ line

      ld = Regexp.last_match(1).split(',').map { |e| e.delete("'") }
      data << {
        id: ld[0].to_i,
        name: ld[1],
        parent_id: (ld[2].present? ? ld[2].to_i : nil),
        lnglat: Point.new(ld[3], ld[4]).to_s
      }
    end

    data.each do |r|
      ChinaRegion.create!(r)
    end
    data = []
  end

  def down
    ChinaRegion.destroy_all
  end
end