Installing Nokogiri via Bundler on Mac (or why did this take two hours?)

If this post saves one person the headache of several hours of trying to build Nokogiri via Bundler on a Mac, maybe my time wasn't wasted, but it was painful.

The setup...
Trying to install Nokogiri 1.6.1 as a dependency for other gems via Capistrano's bundle:install task, I continually ran into "Failed to build gem native extension" error. Scrolling through the errors, the one item that stuck out was "You have to install development tools first."

Although 100% certain my server had Xcode Command Line tools installed (it was recently updated at noted in the App Store), I reinstalled manually and tried to deploy again. Same error.

I then proceeded down the path of using Homebrew to install the various Nokogiri dependencies (e.g. libxml2, libxslt). Deploy...build...fail.

I ran "gem install nokogiri" locally on the server. Build...success. Tried to deploy again...build...fail.

Finally, I dug up the make log for Nokogiri (path below for reference) where I noted a message indicating that "gcc-4.2" was not installed. gcc is installed, but the build script seems specific. Not finding a switch to change the name of gcc, I went brute force:

sudo ln -s /usr/bin/gcc /usr/bin/gcc-4.2

Deploy...build...success! Annoying problem, solved.

Better suggestions welcome.

Make log: /shared/bundle/ruby/2.0.0/gems/nokogiri-1.6.1/ports/x86_64-apple-darwin13.1.0/ext/nokogiri/mkmf.log

Update
After all that, I noticed a warning: "Nokogiri was built against LibXML version 2.8.0, but has dynamically loaded 2.9.1". After trying a few paths, I was able to rectify the warning via the steps in the comments of this :

  1. brew remove --force libxml2
  2. bundle config --delete build.nokogiri
  3. bundle exec gem uninstall nokogiri libxml-ruby
  4. bundle

The commenter notes that Nokogiri 1.6+ now bundle the necessary libraries so there is no need to use the Homebrew versions.