task-1.rb

# Deoptimized version of homework task

require 'json'
require 'pry'
require 'date'
require 'minitest/autorun'

USER_STATS = {
  'sessionsCount' => -> (user) { user.sessions.count },
  'totalTime' => -> (user) { user.sessions_time.sum.to_s + ' min.' },
  'longestSession' => -> (user) { user.sessions_time.max.to_s + ' min.' },
  'browsers' => -> (user) { user.sessions_browsers },
  'usedIE' => -> (user) { user.sessions_browsers.include? 'INTERNET EXPLORER' },
  'alwaysUsedChrome' => -> (user) { user.sessions_browsers.split(',').uniq.all? { |b| b.upcase =~ /CHROME/ } },
  'dates' => -> (user) { user.sessions.map{ |s| s.attributes['date'] }.sort.reverse }
}

class User
  attr_reader :attributes, :sessions

  def initialize(attributes:)
    @attributes = attributes
    @sessions = []
  end

  def add_session(session)
    @sessions << session
  end

  def sessions_time
    @sessions_time ||= sessions.map {|s| s.attributes['time'].to_i}
  end

  def sessions_browsers
    @sessions_browsers ||= sessions.map {|s| s.attributes['browser'].upcase}.sort.join(', ')
  end
end

class Session
  attr_reader :attributes

  def initialize(attributes:)
    @attributes = attributes
  end
end

def parse_user(user)
  fields = user.split(',')
  parsed_result = {
    'id' => fields[1],
    'first_name' => fields[2],
    'last_name' => fields[3],
    'age' => fields[4],
  }
end

def parse_session(session)
  fields = session.split(',')
  parsed_result = {
    'user_id' => fields[1],
    'session_id' => fields[2],
    'browser' => fields[3],
    'time' => fields[4],
    'date' => fields[5],
  }
end

def collect_stats_from_users(report, user, stat, block)
  user_key = "#{user.attributes['first_name']}" + ' ' + "#{user.attributes['last_name']}"
  report['usersStats'][user_key] ||= {}
  report['usersStats'][user_key][stat] = block.call(user)
end

def work(filepath, options = {})
  # Отчёт в json
  #   - Сколько всего юзеров +
  #   - Сколько всего уникальных браузеров +
  #   - Сколько всего сессий +
  #   - Перечислить уникальные браузеры в алфавитном порядке через запятую и капсом +
  #
  #   - По каждому пользователю
  #     - сколько всего сессий +
  #     - сколько всего времени +
  #     - самая длинная сессия +
  #     - браузеры через запятую +
  #     - Хоть раз использовал IE? +
  #     - Всегда использовал только Хром? +
  #     - даты сессий в порядке убывания через запятую +

  GC.disable if options[:disable_gc]

  file_lines = File.read(filepath).split("\n")

  users_objects = []
  sessions_objects = []
  report = {}

  file_lines.each_slice(10000) do |batch|
    batch.each do |line|
      cols = line.split(',')

      if cols[0] == 'user'
        user_attributes = parse_user(line)

        users_objects << User.new(attributes: user_attributes)
      elsif cols[0] == 'session'
        session_attributes = parse_session(line)
        session_object = Session.new(attributes: session_attributes)

        sessions_objects << session_object
        users_objects.last.add_session(session_object)
      end
    end
  end

  all_browsers = sessions_objects.map {|session| session.attributes['browser'].upcase}.sort.uniq.join(',')

  report[:totalUsers] = users_objects.count

  report['uniqueBrowsersCount'] = all_browsers.split(',').size

  report['totalSessions'] = sessions_objects.count

  report['allBrowsers'] = all_browsers

  # Статистика по пользователям

  report['usersStats'] = {}

  users_objects.each do |user|
    USER_STATS.each do |stat, block|
      collect_stats_from_users(report, user, stat, block) 
    end 
  end

  File.write('result.json', "#{report.to_json}\n")
end

class TestMe < Minitest::Test
  def setup
    File.write('result.json', '')
    File.write('data.txt',
'user,0,Leida,Cira,0
session,0,0,Safari 29,87,2016-10-23
session,0,1,Firefox 12,118,2017-02-27
session,0,2,Internet Explorer 28,31,2017-03-28
session,0,3,Internet Explorer 28,109,2016-09-15
session,0,4,Safari 39,104,2017-09-27
session,0,5,Internet Explorer 35,6,2016-09-01
user,1,Palmer,Katrina,65
session,1,0,Safari 17,12,2016-10-21
session,1,1,Firefox 32,3,2016-12-20
session,1,2,Chrome 6,59,2016-11-11
session,1,3,Internet Explorer 10,28,2017-04-29
session,1,4,Chrome 13,116,2016-12-28
user,2,Gregory,Santos,86
session,2,0,Chrome 35,6,2018-09-21
session,2,1,Safari 49,85,2017-05-22
session,2,2,Firefox 47,17,2018-02-02
session,2,3,Chrome 20,84,2016-11-25
')
  end

  def test_result
    work('data.txt')
    expected_result = '{"totalUsers":3,"uniqueBrowsersCount":14,"totalSessions":15,"allBrowsers":"CHROME 13,CHROME 20,CHROME 35,CHROME 6,FIREFOX 12,FIREFOX 32,FIREFOX 47,INTERNET EXPLORER 10,INTERNET EXPLORER 28,INTERNET EXPLORER 35,SAFARI 17,SAFARI 29,SAFARI 39,SAFARI 49","usersStats":{"Leida Cira":{"sessionsCount":6,"totalTime":"455 min.","longestSession":"118 min.","browsers":"FIREFOX 12, INTERNET EXPLORER 28, INTERNET EXPLORER 28, INTERNET EXPLORER 35, SAFARI 29, SAFARI 39","usedIE":true,"alwaysUsedChrome":false,"dates":["2017-09-27","2017-03-28","2017-02-27","2016-10-23","2016-09-15","2016-09-01"]},"Palmer Katrina":{"sessionsCount":5,"totalTime":"218 min.","longestSession":"116 min.","browsers":"CHROME 13, CHROME 6, FIREFOX 32, INTERNET EXPLORER 10, SAFARI 17","usedIE":true,"alwaysUsedChrome":false,"dates":["2017-04-29","2016-12-28","2016-12-20","2016-11-11","2016-10-21"]},"Gregory Santos":{"sessionsCount":4,"totalTime":"192 min.","longestSession":"85 min.","browsers":"CHROME 20, CHROME 35, FIREFOX 47, SAFARI 49","usedIE":false,"alwaysUsedChrome":false,"dates":["2018-09-21","2018-02-02","2017-05-22","2016-11-25"]}}}' + "\n"
    assert_equal expected_result, File.read('result.json')
  end
end