Initial commit

.gitignore

@@ -0,0 +1 @@
+pkg

Manifest

@@ -0,0 +1,15 @@
+config.yml
+init.rb
+lib/yahoo_currency/exchange_rate.rb
+lib/yahoo_currency/yahoo_currency.rb
+lib/yahoo_currency.rb
+Manifest
+Rakefile
+README.rdoc
+test/docs/FAKE-FAKE.csv
+test/docs/JPY-USD.csv
+test/docs/USD-CAD.csv
+test/integration/yahoo_currency_test.rb
+test/mocks/yahoo_currency_mock.rb
+test/test_helper.rb
+test/unit/yahoo_currency_test.rb

README.rdoc

@@ -0,0 +1,61 @@
+=== YahooCurrency
+
+Get the exchange rate for a set of currency codes.
+
+==== The Yahoo! Finance Service
+
+URL to fetch the AUD to USD exchange rate
+
+    http://download.finance.yahoo.com/d/quotes.csv?s=AUDUSD=X&f=nl1d1t1
+
+Although the Yahoo! service supports multiple rates values from one request, 
+this class does not yet support this functionality yet.
+
+  $ curl "http://download.finance.yahoo.com/d/quotes.csv?s=USDCAD=X+JPYUSD=X+GBPUSD=X+USDJPY=X+EURUSD=X&f=nl1d1t1"
+  "USD to CAD",1.0191,"6/18/2008","2:45am"
+  "JPY to USD",0.0093,"6/18/2008","2:45am"
+  "GBP to USD",1.9514,"6/18/2008","2:44am"
+  "USD to JPY",108.085,"6/18/2008","2:45am"
+  "EUR to USD",1.5493,"6/18/2008","2:44am"
+
+==== Features
+
+* So easy to use, even a baby could find out what his currency is trading at.
+
+==== Example
+
+  exchange_rate = YahooCurrency.get_rate!("JPY", "USD")
+  exchange_rate.from #=> "JPY"
+  exchange_rate.to #=> "USD"
+  exchange_rate.rate #=> 0.0111
+  exchange_rate.timestamp #=> Wed Feb 11 22:20:00 +0800 2009
+
+==== References
+
+* http://gummy-stuff.org/forex.htm
+* http://www.thinkruby.org/tags/currency-converter
+* http://finance.yahoo.com/currency 
+* http://gummy-stuff.org/Yahoo-data.htm - tag info (the f parameter)
+
+==== License
+
+Copyright (c) 2009 Global IT Creations Pte. Ltd. http://www.globalitcreations.com/
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+

Rakefile

@@ -0,0 +1,65 @@
+require 'rubygems'
+require 'rake'
+require 'rake/testtask'
+require 'echoe'
+require 'yaml'
+
+APP_NAME = "yahoo_currency"
+APP_URL = "http://github.com/scottbarr/yahoo_currency/tree/master"
+APP_DESCRIPTION = "Fetch currency exchange rates from Yahoo! Finance"
+AUTHOR_NAME = "Scott Barr"
+AUTHOR_EMAIL = "scottb@globalitcreations.com"
+
+#
+# Create a version for this build from the config.yml and the BUILD_NUMBER
+# environment variable.
+#
+def get_version
+  # read the config file
+  config = open("config.yml") {|f| YAML.load(f)}
+
+  # build the version number
+  version_major = config["version"]["major"]
+  version_minor = config["version"]["minor"]  
+  version_build = ENV["BUILD_NUMBER"] ||= "0"
+  "#{version_major}.#{version_minor}.#{version_build}"
+end
+
+Rake::TestTask.new("test:units") { |t|
+  t.pattern = 'test/unit/*_test.rb'
+  t.verbose = true
+  t.warning = false
+}
+
+Rake::TestTask.new("test:integration") { |t|
+  t.pattern = 'test/integration/*_test.rb'
+  t.verbose = true
+  t.warning = false
+}
+
+# setup the gem
+Echoe.new(APP_NAME, get_version) do |p|
+  p.description    = APP_DESCRIPTION
+  p.url            = APP_URL
+  p.author         = AUTHOR_NAME
+  p.email          = AUTHOR_EMAIL
+  p.ignore_pattern = ["tmp/*", "script/*"]
+  p.development_dependencies = []
+end
+
+# define a remove task method so the "test" task isn't breaking my stuff
+Rake::TaskManager.class_eval do
+  def remove_task(task_name)
+    @tasks.delete(task_name.to_s)
+  end
+end
+
+# helper method to remove a task
+def remove_task(task_name)
+  Rake.application.remove_task(task_name)
+end
+
+# remove the original test task
+remove_task :test
+
+task :test => ["test:units", "test:integration"]

config.yml

@@ -0,0 +1,4 @@
+--- 
+version: 
+  major: 0
+  minor: 1

init.rb

@@ -0,0 +1,3 @@
+# require 'lib/yahoo_currency'
+# require 'lib/exchange_rate'
+require 'yahoo_currency'

lib/yahoo_currency.rb

@@ -0,0 +1,2 @@
+require 'yahoo_currency/yahoo_currency'
+require 'yahoo_currency/exchange_rate'

lib/yahoo_currency/exchange_rate.rb

@@ -0,0 +1,12 @@
+class ExchangeRate
+
+  attr_accessor :from, :to, :rate, :timestamp
+
+  def initialize(from, to, rate, timestamp)
+    @from = from
+    @to = to
+    @rate = rate
+    @timestamp = timestamp
+  end
+
+end

lib/yahoo_currency/yahoo_currency.rb

@@ -0,0 +1,50 @@
+require 'net/http'
+require 'time'
+
+class YahooCurrency
+
+  # set the host and path we access the service from
+  HOST = 'download.finance.yahoo.com'
+  PATH = '/d/quotes.csv'
+
+  #
+  # Retrieve the exchange rate for the from and to currency codes.
+  #
+  def self.get_rate!(from, to)
+
+    # create the url
+    http = Net::HTTP.new(HOST, 80)
+    target = "#{PATH}?s=#{from}#{to}=X&f=nl1d1t1"
+
+    # hit the url
+    resp, data = http.get(target, nil)
+
+    # check the response code
+    if resp.code.to_i != 200
+      raise "#{resp.code} #{resp.message}"
+    end
+
+    ExchangeRate.new(from, to, parse_rate(data), parse_timestamp(data))
+  end
+
+  private
+
+  #
+  # The rate is the first field in the CSV
+  #
+  def self.parse_rate(data)
+    data.split(',')[1].to_f
+  end
+
+  #
+  # The timestamp is in the 2 and 3rd fields of the CSV
+  #
+  def self.parse_timestamp(data)
+    # the timestamp will be in M/D/YYYY HH:mm:ampm format
+    ts = (data.split(',')[2] + ' ' + data.split(',')[3]).gsub('"', '').chop
+    return nil if ts == "N/A N/A"
+
+    Time.parse(ts)
+  end
+
+end

test/docs/FAKE-FAKE.csv

@@ -0,0 +1 @@
+"FAKEFAKE=X",0.00,"N/A","N/A"

test/docs/JPY-USD.csv

@@ -0,0 +1 @@
+"JPY to USD",0.0093,"6/18/2008","2:45am"

test/docs/USD-CAD.csv

@@ -0,0 +1 @@
+"USD to CAD",1.0191,"6/18/2008","2:45am"

test/integration/yahoo_currency_test.rb

@@ -0,0 +1,28 @@
+require 'test/test_helper'
+
+class YahooCurrencyTest < Test::Unit::TestCase
+
+  def setup
+    @timestamp = Time.parse("6/18/2008 2:45am")
+  end
+
+  def test_get_rate_usd_aud
+    exchange_rate = YahooCurrency.get_rate!("AUD", "USD")
+    assert_equal "AUD", exchange_rate.from
+    assert_equal "USD", exchange_rate.to
+    assert_not_nil exchange_rate.rate
+    assert_not_nil exchange_rate.timestamp
+  end
+
+  #
+  # Test one or more unknown currency codes
+  #
+  def test_get_rate_fake_fake
+    exchange_rate = YahooCurrency.get_rate!("FAKE", "FAKE")
+    assert_equal "FAKE", exchange_rate.from
+    assert_equal "FAKE", exchange_rate.to
+    assert_equal 0.00, exchange_rate.rate
+    assert_nil exchange_rate.timestamp
+  end
+
+end

test/mocks/yahoo_currency_mock.rb

@@ -0,0 +1,20 @@
+#
+# A mock of the YahooCurrency class
+#
+require  'lib/yahoo_currency'
+
+# Reopen and override the class
+class YahooCurrency
+
+  def self.get_rate!(from, to)
+
+    data = ""
+    # try and open a test csv files
+    File.open("test/docs/#{from}-#{to}.csv", "r") do |infile|
+      data = infile.gets
+    end
+
+    ExchangeRate.new(from, to, parse_rate(data), parse_timestamp(data))
+  end
+
+end

test/test_helper.rb

@@ -0,0 +1,2 @@
+require 'test/unit'
+require 'yahoo_currency'

test/unit/yahoo_currency_test.rb

@@ -0,0 +1,37 @@
+require 'test/test_helper'
+require 'test/mocks/yahoo_currency_mock'
+
+class YahooCurrencyTest < Test::Unit::TestCase
+
+  def setup
+    @timestamp = Time.parse("6/18/2008 2:45am")
+  end
+
+  def test_get_rate_jpy_usd
+    exchange_rate = YahooCurrency.get_rate!("JPY", "USD")
+    assert_equal "JPY", exchange_rate.from
+    assert_equal "USD", exchange_rate.to
+    assert_equal 0.0093, exchange_rate.rate
+    assert_equal @timestamp, exchange_rate.timestamp
+  end
+
+  def test_get_rate_usd_cad
+    exchange_rate = YahooCurrency.get_rate!("USD", "CAD")
+    assert_equal "USD", exchange_rate.from
+    assert_equal "CAD", exchange_rate.to
+    assert_equal 1.0191, exchange_rate.rate
+    assert_equal @timestamp, exchange_rate.timestamp
+  end
+
+  #
+  # Test one or more unknown currency codes
+  #
+  def test_get_rate_fake_fake
+    exchange_rate = YahooCurrency.get_rate!("FAKE", "FAKE")
+    assert_equal "FAKE", exchange_rate.from
+    assert_equal "FAKE", exchange_rate.to
+    assert_equal 0.00, exchange_rate.rate
+    assert_nil exchange_rate.timestamp
+  end
+
+end