Ohai detects data about your operating system. It can be used standalone, but it's primary purpose is to provide node data to Chef.
Ohai will print out a JSON data blob for all the known data about your system. When used with Chef, that data is reported back via node attributes.
Opscode distributes ohai as a RubyGem. This README is for developers who want to modify the Ohai source code. For users who want to write plugins for Ohai, see the wiki:
Before working on the code, if you plan to contribute your changes, you need to read the Opscode Contributing document.
You will also need to set up the repository with the appropriate branches. We document the process on the Chef Wiki.
(Substitude 'ohai' for 'chef')
Once your repository is set up, you can start working on the code. We do use BDD/TDD with RSpec, and soon Cucumber for integration/feature testing, so you'll need to get those installed.
In order to have a dev environment where you can work on Ohai, you'll need to install a few additional gems after setting up the Git repository.
Install the following RubyGems.
gem install rake rspec extlib systemu json
Ohai has some Rake tasks for doing various things.
rake -T rake clobber_package # Remove package products rake gem # Build the gem file ohai-$VERSION.gem rake install # install the gem locally rake make_spec # create a gemspec file rake package # Build all the packages rake repackage # Force a rebuild of the package files rake spec # Run specs
($VERSION is the current version, from the GemSpec in Rakefile)
We use RSpec for unit/spec tests.
Because ohai gathers system information, and we don't know what kind of system we might be running on (yet), we're moving away from specs for integration testing and to cucumber.
(Use the OHAI project)
Ohai - system information application
Adam Jacob (<email@example.com>)
Copyright © 2008 Opscode, Inc.
Apache License, Version 2.0
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