Get Weather of Bloomberg's Top 50 Cities

top50citiesweather.rb

require 'net/http'
require 'rexml/document'

class CityWeather
	attr_reader :state, :city, :high, :low, :condition, :current
	
	def initialize (state, city, high, low, condition, current)
		@state = state
		@city = city
		@high = high
		@low = low
		@condition = condition
		@current = current
	end
end

def get_weather_data(woeid)
	raw_xml = Net::HTTP.get_response(URI.parse(woeid)).body
	doc = REXML::Document.new(raw_xml)
	
	location = CityWeather.new(REXML::XPath.first(doc, '//@region').value, 
		                   REXML::XPath.first(doc, '//@city').value,
				   REXML::XPath.first(doc, '//@high').value.to_i,
				   REXML::XPath.first(doc, '//@low').value.to_i,
				   REXML::XPath.first(doc, '//@text').value,
		                   REXML::XPath.first(doc, '//@temp').value.to_i)
end

def read_woeids
	file = File.open('top50citieswoeids.txt')
	source_trunk = "http://weather.yahooapis.com/forecastrss?w="
	web_addresses = []
	
	file.each do |line|
		web_addresses << source_trunk + line
	end
	web_addresses
end

def time_it(woeids)
	start_time = Time.now
	city_weather = woeids.map{ |woeid| get_weather_data(woeid) }
  
	city_weather.sort_by! { |location| [location.state, location.city]}	
	puts "Time to complete #{Time.now - start_time}s"
	[city_weather, city_weather.max_by(&:current).city, city_weather.min_by(&:current).city]
end

def print(list, high_city, low_city)
	col_width = list.map{|location| location.city.length}.max + 2
	
	puts "State".ljust(col_width) + "City".ljust(col_width) + 
		"High".ljust(col_width) + "Low".ljust(col_width) + 
		"Condition".ljust(col_width) + "Current Temp".ljust(col_width)
	
	list.each do |location|
		puts location.state.ljust(col_width) + location.city.ljust(col_width) +
	             location.high.to_s.ljust(col_width) + location.low.to_s.ljust(col_width) + 
	             location.condition.ljust(col_width) + location.current.to_s.ljust(col_width)
	end
			
	puts "High: #{high_city}"
	puts "Low: #{low_city}"
end

woeids = read_woeids
city_weather, high_city, low_city = time_it(woeids)
print(city_weather, high_city, low_city)

top50citieswoeids.txt

2427690
2471390
2463583
2503863
2522292
2378015
2480201
2430683
2388929
2410128
2487796
2487129
2419946
2394734
2464592
2424766
2465512
2366355
2357024
2414469
2452078
2458833
2457170
2391279
2428344
2438841
2473224
2488042
23393762
2379200
2378426
2475687
2383489
2443945
2367105
2352824
2459115
2490383
2357536
2473475
2354490
2487956
2512636
2487889
2514815
2427665
2490057
2423945
2355942
2478307