console

1.9.3p392 :002 > Postcode
 => Postcode(id: integer, postcode: string, long: decimal, lat: decimal, address: string, bias: string, data: text, tries: integer, updated_at: datetime, created_at: datetime) 
1.9.3p392 :003 > 

postcode_import.rake

desc 'Import PostCodes And Validate'
task :postcode_import => :environment do
  puts "\n\n Importing PostCodes"
 
  file = open('lib/data/postcode.gz')
  gz = Zlib::GzipReader.new(file).read
  arr = []
  gz.each_line do |line|
    arr << line
  end
  
  new_arr = arr.map { |a| a.split(',') }
  lat_long_res = []
  new_arr.each do |row|
    if row[0].include? ' '
      postcode = row[0]
    else
      postcode = row[0][0..3] + " " + row[0][4..-1]
    end
    easting = row[1].to_i
    northing = row[2].to_i
    en_to_ll = Silva::Location.from(:en, :easting => easting, :northing => northing).to(:wgs84)
    lat_long_res << [postcode, en_to_ll.lat.to_f,  en_to_ll.long.to_f]
  end
  lat_long_res.each {|postcode, lat, long| Postcode.where(postcode: postcode, lat: lat, long: long).first_or_create}
end