如何使用JRuby将Rails 2.3.12升级到3.x或4.x版本

Question

I used Jruby version 1.6.5.1 which include Ruby 1.8.7, rails 2.3.12. and gem 1.6.2. How can I upgrade all this versions to higher versions (Jruby 1.7.x, ruby 1.9.x or 2.x and rails 3.x or 4.x)

Thanks in advance.

Answer 1

You can use rvm to manager ruby version

Bellow code lines is use install ruby 1.9.3 on Centos. You can refference it.

curl -L get.rvm.io | bash -s stable
source /etc/profile.d/rvm.sh

rvm install 1.9.3

rvm use 1.9.3 --default 

Answer 2

this will be a multi-step process and largely depends on the gems you're using. it really helps if you happen to have test coverage, otherwise it might get a little painful.

here's shortly what I would do (did some 2.3 upgrades previously) :

• upgrade JRuby to latest 1.7.x it defaults to 1.9.3 but using --1.8 makes it 1.8.7 compatible
• setup Bundler on Rails 2.3 http://bundler.io/v1.11/rails23.html (will help managing the gems)
• attempt to upgrade to Rails 3.2 (review an empty created app to adjust the environment/*.rb, environment.rb, boot.rb etc. accordingly) - some gems might need an upgrade or replacing
• switch off the --1.8 switch for JRuby ... you'll be running with 1.9.3
• (optional) upgrade to Rails 4.x
• (optional) upgrade to JRuby 9.0.x

*each step assumes running tests or somehow testing out the app is in a working state.