A simple Ruby gem to help ensure external dependencies are operational, when booting an application (or anything at all!).
Add this line to your application's Gemfile:
gem 'await_rb'And then execute:
$ bundle
Or install it yourself as:
$ gem install await_rb
Simply execute the Await-Rb rake task for the protocol you'd like to check, and define the command you'd like to execute once the dependency has loaded. For example, if you want to make sure a MySQL server (e.g. 172.20.0.10) is running before you run your Ruby/Rack/Sinatra application, you can run:
bundle exec rake await:tcp host=172.20.0.10 port=3306 && ruby -e "puts 'MySQL is listening.'"By default, Await-Rb will time out after 10 minutes (600 seconds) if a connection cannot be established. To change this, simply pass a new value (in seconds), to the timeout environment variable. e.g.
bundle exec rake await:tcp host=172.20.0.10 port=3306 timeout=300 && ruby -e "puts 'Hello world!'"If the external dependency is running on the local machine, you can omit the host environment variable and it will automatically default to 127.0.0.1
After checking out the repo, run bin/setup to install dependencies. 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 tags, and push the .gem file to rubygems.org.
Bug reports and pull requests are welcome on GitHub at https://github.com/[USERNAME]/await_rb. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.
The gem is available as open source under the terms of the MIT License.
Everyone interacting in the AwaitRb project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.