Satya's blog - Rails 3 upgrade on ubuntu

May 29 2011 16:03 Rails 3 upgrade on ubuntu

Spent several hours yesterday upgrading an Ubuntu running Ruby on Rails 2.x to Rails 3.

Starting with an Apache running passenger, ruby from Ubuntu repositories, and Rails 2.x from gems, we'll end with a fully rvm'd system, bundler, etc.

First upgrade rubygems to 1.6.2 by downloading, because ubuntu rubygems packages are hopelessly outdated:

wget http://production.cf.rubygems.org/rubygems/rubygems-update-1.6.2.gem
sudo gem install rubygems-update-1.6.2.gem
sudo /var/lib/gems/1.8/bin/update_rubygems

Verify with gem -v, which should produce 1.6.2.

Install rvm and other dependencies. You need readline, and the dev libs to compile it. Install it now, save headaches later.

sudo apt-get install git-core tig libreadline-ruby \
    libncurses-dev libreadline-dev

Install rvm via git:

mkdir -p ~/.rvm/src/ && cd ~/.rvm/src && rm \
    -rf ./rvm/ && git clone \
    git://github.com/wayneeseguin/rvm.git && cd \
    rvm && ./install

Add this line to the end of .bashrc. See the rvm web site for details on why and how.

[[ -s "~/.rvm/scripts/rvm" ]] && source "~/.rvm/scripts/rvm"

Install ruby 1.9.2, passenger, and the rails upgrade checker plugin, and set up Gemfile. The first step, i.e. the ruby 1.9.2 install, takes time. This sets the new ruby as the default, installs newest rails and passenger, goes back to old ruby to install the rails upgrade helper plugin, sets 1.9.2 as the default for everyone plus passenger, pulls new Rails skeleton into your app, and installs bundler.

rvm install 1.9.2
rvm 1.9.2 default
gem install rails passenger
rvm system
cd RAILS_ROOT
script/plugin install git://github.com/rails/rails_upgrade.git
rake rails:upgrade:backup 
rvm 1.9.2 --default --passenger
rails new .
# (bunch of fiddling with environment.rb, application.rb, routes.rb)
gem install bundler

Add required gems to Gemfile in RAILS_ROOT, so you get non-broken mysql and rake:

gem 'mysql2', '< 0.3'
gem 'rake', '0.8.7'

Set the Gemfile.lock file with correct permissions. Then install the gems.

touch Gemfile.lock
sudo chown www-data.YOURUSERLOGIN Gemfile.lock
sudo chmod 664 Gemfile.lock
bundle install

Run `bundle check` in a rails application's directory (RAILS_ROOT) to find out what gems to install. It'll tell gem name and version number.

Thanks to http://basedotextend.com/, I found out how to compile openssl support in order to install passenger properly. Compile readline while you're at it:

cd ~/.rvm/src/ruby-1.9.2-p180/ext/openssl
ruby extconf.rb
make
make install

cd ~/.rvm/src/ruby-1.9.2-p180/ext/readline
ruby extconf.rb
make
make install

Now the actual passenger install. This will ask to install some development libraries, so install them using "sudo apt-get install list of packages that it gives" and run it again (i.e. run once to find out what it wants, install the dev libs, run again):

~/.rvm/src/rvm/binscripts/rvmsudo  passenger-install-apache2-module

It should eventually spit out the right Apache config, something like this:

LoadModule passenger_module \
    ~/.rvm/gems/ruby-1.9.2-p180/gems/passenger-3.0.7/ext/apache2/mod_passenger.so

PassengerRoot ~/.rvm/gems/ruby-1.9.2-p180/gems/passenger-3.0.7
PassengerRuby ~/.rvm/bin/passenger_ruby

The LoadModule line should go in /etc/apache2/mods-enabled/passenger.load and the other two will go in /etc/apache2/mods-enabled/passenger.conf. It doesn't matter, both files are loaded, but that's how Apache is organized on Ubuntu.

Remove passenger and readline compilation libraries:

sudo apt-get remove build-essential libcurl4-openssl-dev libssl-dev \
    zlib1g-dev libopenssl-ruby apache2-prefork-dev libapr1-dev \
    libaprutil1-dev libncurses-dev libreadline-dev

If you're using calendar_date_select on Rails3, there's a gotcha. Some weird interaction between git and bundler on rails 3 causes issues, so you have to muck with the Gemfile. First put this in the Gemfile (all one line):

gem 'calendar_date_select', :git =>
'http://github.com/paneq/calendar_date_select',
:branch => 'rails3test'

Then install the source, compile the gem and inject the gem into rvm:

bundle install
cd ~/.rvm/gems/ruby*/bundler/gems/calendar_date_select*
gem build calendar_date_select.gemspec
gem install ./calendar_date_select
# Change Gemfile to:
gem 'calendar_date_select'

You have to switch the gemfile around every time you run bundle install. Ugh.

Last updated: May 29 2011 16:49

Tag: rails3 howto