ios_japanese_documents_downloader.rb

#! /usr/bin/env ruby
# encoding: UTF-8

require 'uri'
require 'json'
require 'open-uri'
require 'openssl'
require 'nokogiri'

def get_documents_info()

  index_uri = 'https://developer.apple.com/jp/documentation/'

  open(index_uri, "r", {:ssl_verify_mode => OpenSSL::SSL::VERIFY_NONE}) do |index_file|

    index = Nokogiri::HTML(index_file)
    index.xpath('//table[@id="documentsTable"]/tr').each do |tr|

      document = {}

      document['id'] = tr.attr('id')
      document['title'] = tr.xpath('td[@class="title"]/div[@class="jp"]/a').first.content
      document['pdf'] = URI.join(index_uri, tr.xpath('td[@class="title"]/div[@class="jp"]/a/@href').first.value)
      begin
        document['date'] = Date.parse(tr.xpath('td[@class="docRevisionDate"]/div[@class="jp"]').first.content)
      rescue ArgumentError => error
        document['date'] = Date.today
      end

      yield document
    end
  end
end

def download_file(uri, path)
  open(uri, "r", {:ssl_verify_mode => OpenSSL::SSL::VERIFY_NONE}) do |remote_file|
    open(path, 'w+b') do |local_file|
      local_file.write(remote_file.read)
    end
  end
end

index_file_name = 'index.json'

if File.exist?(index_file_name) then
  index_file = open(index_file_name, 'r:utf-8')
  index = JSON.load(index_file)
  index_file.close
elsif
  index = {}
end

get_documents_info do |document|

  downloaded_file = index[document['id']]

  if downloaded_file == nil or document['date'] > Date.parse(downloaded_file['date']) then
    begin
      download_file(document['pdf'], "#{document['title']}.pdf")
    rescue
      puts "#{document['title']} has not been downloaded."
    else
      puts "#{document['title']} has been downloaded."
      index[document['id']] = document

      JSON.dump(index, open(index_file_name, 'w:utf-8'))
    end
  end
end