cache_if_slow

Caches slow blocks of code using a cascading configuration.

Installation

Add gem

Add this line to your application's Gemfile:

gem 'cache_if_slow'

And then execute:

$ bundle install

Or install it yourself:

$ gem install cache_if_slow

Usage

Create cache instance

expiry_lookup can be used to set the ttl for a given block of code.

With the below example, if a block of code took 1 -> 5 seconds, e.g. 2 seconds, then that result will be cached for 10 minutes. If it instead took over 10 seconds, then it would be cached for 30 minutes.

def self.cache
  @cache ||= CacheIfSlow.new(expiry_lookup: [
    { slower_than: 1.second, expires_in: 10.minutes },
    { slower_than: 5.seconds, expires_in: 20.minutes },
    { slower_than: 10.seconds, expires_in: 30.minutes }
  ])
end

fetch the result

This operates as a proxy to the Rails.cache.fetch method.

returned_value = self.class.cache.fetch("unique-cache-key") do
  slow_request()
end

Development

After checking out the repo, run bin/setup to install dependencies. Then, run bundle exec rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Testing

Run all specs + standardrb

bundle exec rake

Run only standardrb

bundle exec rake standard

Apply standardrb auto fixes

bundle exec rake standard:fix

Run specs using guard

bundle exec guard

This will auto run the related unit tests while you develop and save files.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/cianmce/cache_if_slow. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the cache_if_slow project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.

TODO

• Update Readme and spec with class method examples