More Freedom with GNU Stow

Jul 04, 2014

stow ruby devops server tutorial

In honour of our friends down South celebrating their independence, let's look at installing a local version of ruby onto a POSIX machine without requiring wrappers like rvm or rbenv. We want to be free to install things where we want, when we want, and how we want. Now that's true freedom.

Install GNU Stow

Okay, you are going to need to install stow system wide for this step. This requires administrative permissions. I promise it's the only thing.

$ sudo apt-get update
$ sudo apt-get install stow -y

Install build tools

Okay, I lied. You'll also need to install build-essential on your machine because we will be compiling and installing packages from source. Some machines don't have the full build suite of compilers and other tools installed.

$ sudo apt-get install build-essential -y

Setup your home directory

$ mkdir ~/.local

It is a dot-directory so that it remains hidden from everyday view. You don't want to see it cluttering up your ls results. Now we setup a structure similar to /usr/local for ease (I believe this is optional, but YMMV).

$ cd ~/.local
$ mkdir bin etc games include lib man sbin share src

Update your PATH

Create a .bash_profile to point to the binaries in the .local directory.

$ echo "export PATH=$HOME/.local/bin:$PATH" >> ~/.bash_profile
$ source ~/.bash_profile

Create a Stow directory

Now create a directory in your .local directory to hold everything that stow will manage.

$ mkdir ~/.local/stow

Install Ruby 2.1.2

First download the source tarball.

$ wget http://cache.ruby-lang.org/pub/ruby/2.1/ruby-2.1.2.tar.gz

Then unpack the tarball.

$ tar xfz ruby-2.1.2.tar.gz

Now configure, compile and install it.

$ cd ruby-2.1.2
$ ./configure --prefix=/home/typicalrunt/.local/stow/ruby-2.1.2
$ make
$ make install

Activate the package

$ cd .local/stow
$ stow ruby-2.1.2

Check the installation

$ which ruby
/home/typicalrunt/.local/bin/ruby
$ ruby -v
2.1.2p95

Install some gems

You'll notice that you do not have to use sudo privileges in order to install gems. This is because all gems are stored within the .local/stow/ruby-2.1.2 directory.

$ gem install bundler

Check the Installation

$ which bundle
$

Uh-oh. Something's wrong. Bundler doesn't seem to be available as a command. The issue is that Stow hasn't symlinked it into the .local/bin directory. All we do is tell stow to restore the symlink.

$ cd .local/stow
$ stow --restore ruby-2.1.2

And now all the new gem binaries are visible in the .local/bin directory.

$ which bundle
/home/typicalrunt/.local/bin/bundle

Upgrading or Downgrading Ruby

Now let's have some fun. Let's try installing Ruby 2.0.0 and seeing how Stow handles it. For our use case, it should be fairly easy to switch between ruby versions for the local user.

$ wget http://cache.ruby-lang.org/pub/ruby/2.0/ruby-2.0.0-p481.tar.gz
$ tar xfz ruby-2.0.0-p481.tar.gz
$ cd ruby-2.0.0-p481
$ ./configure --prefix=/home/typicalrunt/.local/stow/ruby-2.0.0-p481
$ make
$ make install

Ruby 2.0.0 is now setup and we need to deactivate Ruby 2.1.2 and activate Ruby 2.0.0.

$ cd ~/.local/stow
$ stow -D ruby-2.1.2
$ stow ruby-2.0.0-p481

Now we check the install

$ ruby -v
2.0.0-p481

Yay! But what about the gems? They are tied to the ruby version that was activated by Stow, so activating another version of Ruby means that you will need to reinstall the gems for this version of Ruby.