[currency_rate_monitor.rb] Monitoring NZD rate and notify you while the rate drops down the limit you set.

currency_rate_monitor.rb

#!/usr/bin/env ruby

require 'net/http'
require 'nokogiri'

# Get the rate data from boc page.
def getRate
  url = 'http://www.boc.cn/sourcedb/whpj/'
  data = Nokogiri::HTML.parse(Net::HTTP.get(URI(url)))

  nz_line = data.css('tr')[18].css('td')

  rate = nz_line[4].text
end

# Notify in the iterm2.
def notify rate, limit = 460
  if rate.to_f < limit
    title = "It is the time!"
    message = "Rate : " + rate.to_s
    exec 'noti -t ' + title + '  -m ' + message
  end
end

# Record message.
def log message
  f = File.new "output.log", 'a+'
  f.write message + "\n"
  f.close
end

# Let's go!
loop do
  rate = getRate
  notify rate
  log rate
  sleep 240
end

# end of this file.