Category: Ruby

Ubuntu 12 : RVM : Default Gemset not Working/Setting

When setting up a Ruby/Rails development environment utilizing Ubuntu 12.04 LTS you may find yourself running into issues with setting your RVM default Gemset.

I attempted to set the default Gemset using every possible combination of the command rvm –default use 1.9.3-p286@corerivalry but every time I closed my terminal and re-opened it my default Ruby was set, but my Gemset was continually being set back to (default).
After much searching and frustration I ran into the –rvmrc command which creates a file (.rvmrc) that specifies the Ruby version as well as the Gemset to use for an individual project. After running the command, each time I opened my terminal in my Rail application’s root folder my Ruby and Gemset are exactly what I intend them to be.
The command:
rvm use 1.9.3-p286@rails3 --rvmrc

Ruby: Mint12 Sqlite3 Install Issues (sqlite3.h)

On the latest version of Linux Mint 12 (the Linux platform I prefer for Ruby development) I ran a bundle install on a small application using Sqlite3 and ran into the following error message. After a little Google search I found that my installing Sqlite3 did not give Gem all the build files it requires to build the Sqlite3-ruby gem with native extensions. So if you are running into the same issue make sure you run the following commands prior to running bundle install.

<<<>>>

sudo apt-get install sqlite3
sudo apt-get install libsqlite3-dev

<<<>>>

Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

/home/tim/.rvm/rubies/ruby-1.9.2-p290/bin/ruby extconf.rb
checking for sqlite3.h… no
sqlite3.h is missing. Try ‘port install sqlite3 +universal’
or ‘yum install sqlite-devel’ and check your shared library search path (the
location where your sqlite3 shared library is located).
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers. Check the mkmf.log file for more
details. You may need configuration options.

Provided configuration options:
–with-opt-dir
–with-opt-include
–without-opt-include=${opt-dir}/include
–with-opt-lib
–without-opt-lib=${opt-dir}/lib
–with-make-prog
–without-make-prog
–srcdir=.
–curdir
–ruby=/home/tim/.rvm/rubies/ruby-1.9.2-p290/bin/ruby
–with-sqlite3-dir
–without-sqlite3-dir
–with-sqlite3-include
–without-sqlite3-include=${sqlite3-dir}/include
–with-sqlite3-lib
–without-sqlite3-lib=${sqlite3-dir}/lib
–enable-local
–disable-local
Gem files will remain installed in /home/tim/.rvm/gems/ruby-1.9.2-p290@CorDev1.9.2/gems/sqlite3-1.3.6 for inspection.
Results logged to /home/tim/.rvm/gems/ruby-1.9.2-p290@CorDev1.9.2/gems/sqlite3-1.3.6/ext/sqlite3/gem_make.out

Ruby: Mint12 Nokogiri Install Issues (libxml2)

If you are running into errors when installing the Ruby Gem Nokogiri and the error you are getting has to do with the library ‘libxml2’ not being available you will need to execute the following commands to fix it.

  1. sudo apt-get install build-essential

  2. sudo apt-get install libxslt-dev libxml2-dev

  3. bundle install

Original Error Message Reference:

checking for libxml/parser.h… no
—–
libxml2 is missing.  please visit http://nokogiri.org/tutorials/installing_nokogiri.html for help with installing dependencies.
—–
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

RVM Application Specific Gemset

Step 1: Setup your Ruby 1.9.2-head

$ rvm 1.9.2-head
WARN: ruby ruby-1.9.2-head is not installed.To install do: ‘rvm install ruby-1.9.2-head’

Step 2: Install the utilities need to build the head

$ sudo apt-get install bison
$ sudo apt-get install autoconf

Step 3: Install your Ruby 1.9.2-head

$ rvm install ruby-1.9.2-head

Step 4: Create your new GemSet

$ rvm gemset create corerivalry

RVM, Ruby, Rails on Linux Mint

Step 1: First we need to install all the required libraries

$ sudo apt-get install curl git-core build-essential zlib1g-dev libssl-dev libreadline5-dev

Step 2: Install RVM

$ bash < <( curl http://rvm.beginrescueend.com/releases/rvm-install-head )

Step 3: mint 10 does not have a .bashrc file so one needs to be added and then RVM specific lines added

$ sudo touch .bashrc
$ sudo gedit .bashrc
(Add line to .bashrc file)
if [[ -s "$HOME/.rvm/scripts/rvm" ]]  ; then source "$HOME/.rvm/scripts/rvm" ; fi

Step 4: close the current terminal and open a new one in order to load the new commands

Step 5: verify RVM has been installed by running you should get back a description of the application written by the author

$ rvm notes

Step 6: now you can install the ruby version of your choice, I am using 1.9.2 so it is compatible with Rails 3

$ rvm install 1.9.2

Step 7: once installed you will need to set the default ruby version to be used by RVM

$ rvm --default ruby-1.9.2

Step 8: verify that the version you selected is now accessible via the standard ruby command

$ ruby -v

Step 9: then use the gem command to install the rails version of your choice

$ gem install rails

Step 10: install MySQL

$ sudo apt-get install libmysql-ruby libmysqlclient-dev
$ gem install mysql2