rails application working with different version

I heard about one thing, which is related with rails version. The thing is ,i created a ruby on rails application with rails version 3.1. So we can execute the same rails application on another different rails version by changing one command via console. i think this is related with the installation of rails with RVM(ruby version manager)? how is it possible?

i used this link for the ruby on rails setting up on ubuntu http://ryanbigg.com/2010/12/ubuntu-ruby-rvm-rails-and-you/. This link also with RVM.

But how is the same possible ?

**can anyone have another link. which using we can run the rails application on different rails version? **

I heard about one thing, which is related with rails version. The thing is ,i created a ruby on rails application with rails version 3.1. So we can execute the same rails application on another different rails version by changing one command via console. i think this is related with the installation of rails with RVM(ruby version manager)? how is it possible?

Rvm allows you to have different versions of ruby. While it does also allow you to manage multiple sets of gems, you don’t need it for that. Rails 3 uses bundler by default which makes it super easy to specify which versions of gems your app uses (including the rails gems)

Fred

Thanks fred

i saw that bundler. u mean (bundle install commad). so how to use this via console. which command is used for changing this version. can u plz specify that?

Thanks

amvis

It is not clear exactly what you are trying to do. Are you trying to
run an existing rails app using a different version of rails? If so
then you need to update the app to be compatible with that version,
and specify the version of Rails you want in Gemfile.

If you are a beginner, have you worked through some tutorials which
will show you how to use bundler as well as to introduce you to the
basics of rails. railstutorial.org is good and is free to use online.

Colin

Thanks for the reply

colin, a simple thing. Now am using rails version is 3.1.1 . i had setup the ruby on rails on my system with RVM( http://ryanbigg.com/2010/12/ubuntu-ruby-rvm-rails-and-you/.) so we have an application which created with rails older version 2.3.6. my question is now how to run this older application on my new setup. can u/anyone specify how to rectify this?

Thank you

vishnu

I don't know how RVM works, but if my only problem was to specify
which version of Rails to use, I'd modify my environment.rb file with
     RAILS_GEM_VERSION = '3.1.1' unless defined? RAILS_GEM_VERSION

... and see if it breaks.

Have a look in the rvm documentation about gemsets. Using a gemset
you can install rails 2.3.6 and whatever versions of other gems that
application needs, then the app should run happily.

Colin

Also <https://rvm.beginrescueend.com/workflow/rvmrc/#project> could be
a good starting point to handle multiple projects having different
gemsets.

I have an isolated gemset for every single project.

At start of a project I create the project dir and run `rvm use
<rubyversion>@<projectname> --create --rvmrc` go one dir level upwards
do again `rvm use <rubyversion>@<projectname>` then `rails new
<projectname>`

I have to say, that rails 3.1 is in my default gemset, also is bundler.

If I have to use another version of rails I do `gem uninstall rails`
first in the corresponding gemset and then `gem install rails
<version>`. Since I handle my gems with bundler in rails 2.x all other
steps are the same.

Bye
Norbert