gem_package fails in Ruby 1.9.3 - undefined method 'full_name' for nil

Question

I'm using Chef to set up a node running Ubuntu 12.04. I wanted to use Ruby 1.9.3, including for Chef, and I'm using this custom bootstrap file I found to accomplish it. (I previously tried using RVM in conjunction with Chef, and found that it caused problems at every turn - I was hoping this would be less error-prone.)

When I run the chef-client on this node, it reaches the point of attempting to install my Rails application, tries to install Bundler, and fails, thus:

Recipe: <Dynamically Defined Resource>
  * gem_package[Bundler] action install
================================================================================
Error executing action `install` on resource 'gem_package[Bundler]'
================================================================================


NoMethodError
-------------
undefined method `full_name' for nil:NilClass


Resource Declaration:
---------------------
# In /var/chef/cache/cookbooks/application_ruby/providers/rails.rb

162:     gem_package gem do
163:       action :install
164:       source src if src
165:       version ver if ver && ver.length > 0
166:     end
167:   end



Compiled Resource:
------------------
# Declared in /var/chef/cache/cookbooks/application_ruby/providers/rails.rb:162:in `block in install_gems'

gem_package("Bundler") do
  provider Chef::Provider::Package::Rubygems
  action [:install]
  retries 0
  retry_delay 2
  package_name "Bundler"
  version ">1.3"
  cookbook_name "tiptap_api"
end

To attempt to isolate the problem, I placed the following call to gem_package in the recipe before the deployment attempt:

gem_package 'Bundler' do
  version '>0'
  action :install
end

This, too, fails, in the same way.

I found that the gem executable installed by apt-get was actually named gem1.9.1. I thought that this might be the problem, and renamed it to gem. Once that was done, I could run sudo gem install bundler normally and without any problems, but the chef-client still produces this error.

What's going on, how can I fix it, and why is this error message so terrible?

Answer 1

From your stack trace, it seems like you want to install a gem called Bundler. However, this gem doesn't exist which results in the error you observe. You probably want to install the bundler gem instead. Case generally matters in the Ruby world :)

While it is true that the error message is rather misleading, the reason for that is probably that the case of a non-existing gem is not explicitly checked by Chef and thus assumptions in later stages of the code just break resulting in the strange error.

This in turn might be considered a bug in Chef that you might want to report on http://tickets.opscode.com/ (at least if that still is an issue in the most current version of Chef, I haven't checked that).