带有rbenv的多个Rails应用和Ruby版本

Question

I have multiple Rails apps from 3.2.14 to 3.2.18 in my development environment. I'm using Ruby 1.9.3 (yes, I know) for these apps and it's installed and managed via rbenv. I'm about to build a couple of new apps with Rails 4.1 and Ruby 2.1. My question is, what is the best way to handle installing multiple versions of Ruby using rbenv. Currently 1.9.3 is set to global, but I want different Rails apps (4.1) to use Ruby 2.1.

I guess I'm a bit behind the curve with Ruby management so I could use a hand here. Again, looking to have multiple Rails apps (different versions 3.2.14-4.1.x) and multiple Ruby instances to support each app.

I appreciate the help in advance.

Answer 1

Create a .ruby-version file in your application root directory and specify the ruby version you want. For instance, if you want one application to use 1.9.3 and the other 2.1.0, you'll have a .ruby-version file each in those two applications, specifying the version:

/application1/.ruby-version
1.9.3

/application2/.ruby-version
2.1.0

Update

For every installed version of ruby, you'll have a shims directory which will house all your gems for that particular version. When you switch between ruby versions, rbenv will simply set the environment variables to the one you select.

In the example above, I set the local ruby version for the directory ruby_cookbook to 2.1.2 and a gem list will only show gems installed for 2.1.2.

I also created a .ruby-version with ruby version 1.9.3-p547 in my try_stuff directory. As you can see, gem list only shows gems installed for 1.9.3.

The gems you install are specific to the current version of ruby.

If your project root has a .ruby-version file, your environment will automatically set the current ruby version to the one specified. So, yes, your production environment will need the version you mention in your .ruby-version . If you use git for source control, you can add that file to your .git-ignore and you won't see it in your prod version.