Fxer is an exchange rate calculator, using the European Central Bank's rates covering the last 90 days.
Add this line to your application's Gemfile:
gem 'fxer'
And then execute:
bundle
Or install it yourself as, replacing the version numbers:
gem build fxer.gemspec
gem install fxer-1.2.3.gem
Fxer includes a quick and simple way of obtaining an exchange rate via a separate namespace:
ExchangeRate.at(Date.today, 'EUR', 'AUD')
# => 1.4732
For situations where you need more control, the Fxer namespace provides configuration:
exchanger = Fxer::Exchange.new.configure do |config|
config.permissive = true
config.source = :ecb
config.store = "/my/path/"
end
exchanger.convert_at_date(Date.today, 'GBP', 'USD')
# => 1.309507859949982
Fxer by default uses the most recently available data at or before the date indicated. Setting permissive to false changes that, in effect a strict-mode, and an error will be raised if a date doesn't have corresponding data.
Fxer is designed to accommodate code for additional sources
of exchange rate data. Source can only be :ecb
as of now.
The configuration of store allows you to indicate where you have locally stored your exchange data file, so that Fxer does not need to download that data to determine the rate.
fxer also provides an executable for getting rates in Bash:
FXER_RATE_DATA_PATH="/my/path" fxer "2017-07-18" NOK HKD
# => 0.9689571804652662
where the environment variable for local file hosting is optional.
And fxer will download new ECB data for you, in either Ruby or Bash:
ENV['FXER_RATE_DATA_DIRECTORY'] = "/my/path/"
Fxer::Fetcher::Ecb.download
FXER_RATE_DATA_DIRECTORY="/my/path/" fxer-fetcher ecb
After checking out the repo, run bin/setup
to install dependencies.
Then, run bundle exec rspec spec
to run the tests.
You can also run bin/console
for an interactive prompt that
will allow you to experiment.
Until this is pushed to RubyGems and GitHub, there is no defined development process.
Bug reports and pull requests will be welcome once fxer is live at https://github.com/samnissen/fxer.
The gem is available as open source under the terms of the MIT License.