Capistrano::Rbenv::Install

Capistrano plugin for lightweight rubies management with rbenv.

Works with Capistrano 3 (only). For Capistrano 2 support check this repository (version 1.x of capistrano-rbenv gem).

Installation

Install by adding the following to the Gemfile:

gem 'capistrano', '~> 3.2.1'
gem 'capistrano-rbenv', '~> 2.0' # required
gem 'capistrano-rbenv-install', '~> 1.2.0'

then:

$ bundle install

Configuration and usage

The following goes to Capfile:

require 'capistrano/rbenv_install'

This plugin heavily relies on capistrano-rbenv config options. So make sure to properly setup capistrano-rbenv and you'll be good.

For example, in config/deploy.rb:

set :rbenv_ruby, '2.0.0-p247'

Other than that, this plugin does not need any setup.

Run:

$ bundle exec cap production deploy

And watch ruby being installed.

Purpose

Installing software packages on servers is called provisioning. Installing and managing rubies falls into that domain, and is best done with a proper tool like chef, puppet, ansible or something else.

Why this plugin then?

  • Capistrano is a great tool (written in ruby btw) so, when there's a need, installing rubies with it should be easy too
  • not everyone knows (or has time to learn) how to use provisioning tools mentioned above
  • sometimes installing ruby manually is just easier than fiddling with your chef cookbooks. Instead of manually, you can do it with this plugin now

Imagine you want to quickly deploy a ruby 1.9.2 app to a server that already has one or more ruby 2.0.0 apps. "Oh, let's just quickly update our cookbooks" - yea right! I'd rather manually ssh to the server directly and run rbenv install 1.9.2-p320. But I don't want to manually ssh to the server too. In that case I just can install capistrano-rbenv-install and forget about it altogether.

What it does

It only does the bare minimum that's required for Capistrano to work. That's why it's a plugin for lightweight ruby management.

It makes sure that:

  • rbenv and ruby build are installed (installs them using git)
  • ruby specified with :rbenv_ruby option is installed
  • bundler gem is installed

What it does NOT do

It does not:

  • manage ruby gems
    bundler is installed by default and that's pretty much it.

  • does not install ruby dependency packages
    (git-core build-essential libreadline6-dev etc ...). You should probably install/provision those some other way.

  • does not manage rbenv plugins
    It only installs ruby build for the purpose of installing ruby.

  • does not setup rbenv for direct use on the server via the command line
    Example: sshing to the server and manually running ruby commands is not supported.

More Capistrano automation?

Check out capistrano-plugins github org.

Thanks

@yyuu and the original capistrano-rbenv project for inspiration

License

MIT