In every setup describing a configuring an environment with rbenv and Bundler, the instructions are always to install bundle as a system gem, using gem install bundler. Often, they'll also recommend rbenv-bundler rbenv plugin, but the maintainers of rbenv discourage this.
What's not described is how to install Rails. Initializing a new Rails project creates a basic Gemfile for bundler. However, in order to initialize a Rails project, one needs to have Rails installed. It seems weird and even wrong to make a directory, write a basic Gemfile that includes Rails, run bundle install, and then initialize Rails to the current directory. In fact, I doubt that would even work well, if it worked at all.
So, does Rails need to be installed as a system gem with gem install rails? If so, how does one manage multiple versions of Rails, particularly with rbenv?
It totally makes sense to NOT install rails as system gem.
Without messing up rbenv or other ruby version manager you use, below are brief steps to create (initialize) a new Rails app from a directory with a Gemfile:
mkdir rails_app
cd rails_app
vi Gemfile # Edit it to include a rails version you need
bundle --path vendor # Wait for bundler to finish
bundle exec rails new ./
The last step would ask: Overwrite /path/to/rails_app/Gemfile? (enter "h" for help) [Ynaqdh]. Input y to get the default Rails Gemfile content.
Note: the above steps specify the local vendor directory (inside the rails app folder) to avoid installing gems to system global scope.
Answer is no, you don't install rails as system gem. Create a project folder, add .ruby-version file and add the ruby version you would like in this file i.e. 2.3.0. rbenv uses the version specified in this file and it won't be system's ruby.
Now you can do gem install bundler from this directory and create Gemfile and add your rails version. Now run bundle install and roll it on the tracks of RAILS.....
Force rails to vendor gems.
$ mkdir foo
$ cd foo
$ bundle config --local path vendor
$ rails new .
Related
I used to use rvm and I want to start trying out rbenv.
From what I understand, rbenv does not have the same isolation built in when it comes to gems, it is only managing your ruby versions.
I know there is a rbenv addon that handles gems, but I dont' NEED to get it correct?
I can still download gems locally to my project and use bundle exec for each command?
Is there a short cut that I don't have to be so verbose when typing my commands?
Please explain the workflow as I dont' want to assume anything.
Update
I'm confused how to get the gems loaded into a separate folder.
Here's what I recommend:
Use rbenv for multiple Ruby version management, no customizations needed
a ruby installer plugin is now included with rbenv
it also handles ruby executable shims automatically, don't need to rbenv rehash anymore
it loads really fast (rvm has a noticable load time on shell startup)
Use bundler to dynamically resolve gems at runtime (options below)
it's fast enough anyways
don't need a special gem solution, bundler comes included /w Ruby now
Options to invoke bundler dynamically (I recommend the last one):
use bundle exec in front of every ruby executable
variant: create alias be='bundle exec'
create bundle binstubs <LIST GEM EXECUTABLES YOU WANT> for each project
use bin/ in front of every ruby executable to call the binstubs
do #2 and then set up .git/safe
lets you manually allow PATH lookups to the bin/ folder while in that project root
don't need to type bin/ anymore
Now multiple gem versions will all be installed into the same Ruby version bucket, and you let bundler dynamically add the right versions to the load path before every startup.
I'm trying to figure what version of rails I got installed.. If I run on it on my home directory:
cd ~
rails -v
I get
Rails 3.2.13
However if I run it on the home directory of a ruby on rails project I just cloned:
cd /path/to/RoR/project
rails -v
I get
git://github.com/seyhunak/twitter-bootstrap-rails.git (at bootstrap3) is not checked out.
Please run `bundle install`
I'm confused.. why would it point out a missing bootstrap gem when I'm only looking for the rails version?
Rails version is declared inside your Gemfile. If you navigate to folder containing Gemfile, RVM automatically switches to rails version specified in this folder (it does the same for Ruby version as well!).
Since you didn't run bundler, Gemfile.lock file is not valid and RVM cannot be sure it contains the right version of rails (some dependencies may require rails to be updated - for bundler rails is just a gem as any other). THat's why it asks you to run bundle.
Hope it makes sense. :)
TL;DR
Don't bother with gemsets; multiple versions of a gem may be installed concurrently.
When necessary, specify which version to execute using $ gem-based-binary _version_ args notation.
Use bundle exec when you have a Gemfile specifying the version.
gem install rails -v 3.2.13
rails _3.2.13_ new Project2
cd Project2
bundle exec rails server
UPDATE: 2015-06-04
I wrote this question three years ago. Partly, it was based on a false assumption, and partly the situation has changed since then. With appreciation to #indirect for his original answer, I want to call attention to #kelvin's newer (less upvoted) answer, summarized above.
My false assumption: Only a single version of a gem could be installed at a time, hence the need for gemsets to isolate the namespace. Not true. Multiple versions of a gem may be installed concurrently. The most recent one will be used when invoked from a command line, unless you have a Gemfile specifying the version constraints and invoke the command via bundle exec, or specify the version as its first argument.
See also How can I call an older version of a gem from the commandline? re: the underscore-version notation.
Original question:
I have multiple projects going on using different versions of Rails. I have a workflow (described below) for creating projects using specific versions of rails, and keeping the projects isolated from each other. I'd like to experiment with other workflows, in particular, using rbenv instead of RVM, but it's not clear how to do so.
QUESTION: What is the best current practice for creating multiple rails projects, each using a different version of rails, when making use of rbenv and bundler, as opposed to rbenv-gemset or rvm?
USE CASE: I have two rails projects, called ProjectA and ProjectB. ProjectA is developed using one version of rails ("RailsA"), whereas ProjectB uses a different version ("RailsB"). How do I manage having both versions installed?
THE GEMSETS APPROACH: When I first started with Rails development, I used RVM. In addition to supporting multiple, concurrent installations of ruby, RVM supports having multiple Named Gem Sets. Each project has its own independent collection of gems (including rails itself) called a gemset:
rvm gemset create RailsA
rvm gemset use RailsA
# RailsA. Note: My question is not version-specific.
gem install rails --version 3.0
rails new ProjectA
cd ProjectA
rvm --rvmrc use `rvm current`
vi Gemfile
bundle install
cd ..
## Now do the same for ProjectB
rvm gemset create RailsB
rvm gemset use RailsB
gem install rails --version 3.2
rails new ProjectB
cd ProjectB
rvm --rvmrc use `rvm current`
vi Gemfile
bundle install
Note: The very creation of the project folders should be done (IMHO) by a rails new command using the desired version of rails, since the skeleton files change from version to version. (Perhaps I should revisit this premise?)
THE BUNDLER APPROACH: I've been playing with using rbenv instead of RVM, but I don't understand the workflow as clearly. In the README.md, Sam Stephenson writes that "rbenv does not ... manage gemsets. Bundler is a better way to manage application dependencies." There is a plugin (rbenv-gemset) for getting the same results as rvm's gemsets, but Sam clearly favors using Bundler instead. Unfortunately, he doesn't elaborate on what the workflow would look like. Even the Bundler website doesn't explicitly connect all the dots of how to isolate one project from another. Several blogs and gists come to the rescue, suggesting the following ~/.bundle/config file:
---
BUNDLE_PATH: vendor/bundle
(BTW, I'm not sure what the "---" is about. The docs make no mention of it and it doesn't seem to make a difference.)
This effectively gives each rails project its own gemset, storing the gems in ProjectX/vendor/bundle/. In fact, rails itself will be (re-)installed there, making the project completely independent of the rest of my environment, once I run bundle install.
But the elephant in the room is the chicken-and-egg problem of creating the rails project folder in the first place!! In order to create the ProjectA folder using RailsA, I need to install rails (and its numerous dependencies) first. But when I want to create ProjectB, I must then switch to using RailsB. Without gemsets, I must do some serious upgrading/downgrading. Not cool.
A possible solution is simply not to worry about what version of rails I use to create the ProjectX folder. If I then use rails 3.0 to create a 3.2 project, I could just manually create the app/assets tree. But that just irks me. Ain't there a better way?
Most people solve this by installing the rails gem first via gem install rails. If you refuse to do that for some reason, you can opt out of the automatic bundling that Rails attempts to do for you. This will work completely regardless of your ruby management system.
mkdir myapp
cd myapp
echo "source :rubygems" > Gemfile
echo "gem 'rails', '3.2.2'" >> Gemfile
bundle install --path vendor/bundle
bundle exec rails new . --skip-bundle
When prompted, type "y" to replace your Gemfile with the default Rails one (or not, as you prefer). Then, once it's done:
bundle install
You're done, and you have boostrapped a new rails app with the version of your choice without installing the rails gem into rubygems.
Suppose you have rails 3.1.0 installed, but you want to create a new project using rails 3.2.13 which is not installed.
Let's say you want the new project to be in ~/projects/Project2.
gem install rails -v 3.2.13
cd ~/projects
rails _3.2.13_ new Project2
This will create the Gemfile for you, locked to the version of rails you specified on the command-line.
I deliberately omitted the idea of keeping a separate copy of gems for the new project, because that goes against the Bundler philosophy, which is to have all gems installed in one place. When you run rails, Bundler will pick the correct gem versions automatically from that central location. That means a project can share gems instead of installing a fresh copy for itself. (Note, however that each version of ruby you install will have its own gems. This is a good thing because native extensions likely won't work across ruby versions.)
You do have to be a bit more aware, because most commands, like rake, will load the newest version of rake that you have installed. You'll need to run bundle exec rake ... to make sure the correct version is loaded. Usually I'll run bundle exec for all commands except rails. You can create an alias to make it shorter (I use bex). To automate this with gem executables, you can use rbenv-binstubs, but you still have to be aware that running non-gem executables like ruby and irb won't automatically use the Gemfile.
Sidenote: rails new will run bundle install, which will check for the newest version of the dependencies. If you want bundler to try to use currently installed gems that satisfy the dependency requirements, you can skip the bundle install with rails new --skip-bundle, then run bundle check in the app dir.
Sidenote 2: suppose you want to use a ruby version for Project2 (e.g. 2.1.8) that's different from the default (e.g. 2.3.0). In that case, running gem install as specified above will install the gems under 2.3.0, which is a waste of time because you'll need to install the gems again under 2.1.8. To solve that problem, you can force the commands to use the preferred version via environment variable:
RBENV_VERSION=2.1.8 gem install rails -v 3.2.13
cd ~/projects
RBENV_VERSION=2.1.8 rails _3.2.13_ new Project2
echo 2.1.8 > Project2/.ruby-version
You could use rbenv shell to set the variable, but I only recommend that if you don't want rbenv to auto-switch based on .ruby-version files for the duration of that shell. It's very easy to forget that you have the variable set, and when you cd to a different project, it won't be using the version you expect.
There's a good recent post on exactly the topic of gemsets / bundler here http://rakeroutes.com/blog/how-to-use-bundler-instead-of-rvm-gemsets/ Good background you can apply to your rbenv setup.
This is a very odd one and I'm not sure how to proceed.
Basically, I am able to install gems and use them normally within any folder except those created with rails. It's very very odd. It's difficult to explain so maybe this console output will explain
passenger#rubyserve:~/railsapps$ ls
app test_application testing
passenger#rubyserve:~/railsapps$ rails -v
Rails 3.2.2
passenger#rubyserve:~/railsapps$
passenger#rubyserve:~/railsapps$
passenger#rubyserve:~/railsapps$ cd app/
passenger#rubyserve:~/railsapps/app$ ls -a
. app config.ru doc Gemfile.lock lib public README.rdoc test vendor
.. config db Gemfile .gitignore log Rakefile script tmp
passenger#rubyserve:~/railsapps/app$
passenger#rubyserve:~/railsapps/app$
passenger#rubyserve:~/railsapps/app$ rails -v
The program 'rails' is currently not installed. To run 'rails' please ask your administrator to install the package 'rails'
passenger#rubyserve:~/railsapps/app$
It makes bugger all sense. When outside my rails folder, I can call rails to make a new application but once within, rails isn't detected. This is the same for all gems including bundler.
My first thought was that somehow, rails had some specific gem folder hidden away, so I done my gem install from within the rails project, however this didn't work either.
Any thoughts?
My setup is ubuntu server 10.10 (I know, i know)
Ruby 1.9.2
gem 1.8.17
and I'm using the latest rvm from wayneeseguin.enter code here
This type of problem some time occurs i think u can save a lot of time by installing and using RVM
After installing RVM create gemset directory every time whenever you create separate project. e.g you create application blog first you create gemset directory with giving this command
rvm gemset create blog
then you should use this gemset directory and also ruby version as well e.g you have install ruby 1.9.2 then use this command
rvm use ruby-1.9.2#blog
after that go into directory of blog application and install this gem
gem install bundler
and also then bundle install. so all local gem will be installed into this blog directory under rvm and there will be no conflicts will be appear.But keep one thing in mind if your platform is ubuntu then this will work
Is it possible to use multiple versions of rails using rbenv (e.g. 2.3 and 3.1)? This was easy with gemsets in rvm, but I'm wondering what the best way is to do it now that I've switched to rbenv (also, I'm looking for a way to do it without rbenv-gemset).
not sure if you got an answer to this, but I thought I'd offer what I did and it seemed to work.
So once you get rbenv installed, and you use it to install a specific ruby version, you can install multiple versions of rails to for that ruby.
STEP 1. Install whatever version(s) of rails you want per ruby version
% RBENV_VERSION=1.9.2-p290 rbenv exec gem install rails --version 3.0.11
By using the "RBENV_VERSION=1.9.2-p290" prefix in your command line, you're specifying which ruby rbenv should be concerned with.
Then following that with the "rbenv exec" command, you can install rails. Just use the version flag as in the example to specify which version you want. Not sure if you can install multiple versions in one shot, but I just run this command as many times as needed to install each version I want.
Note: This will all be managed within your rbenv directory, so it's perfectly safe and contained.
STEP 2. Build a new rails project by specifying the rails version you want.
% RBENV_VERSION=1.9.2-p290 rbenv exec rails _3.0.11_ new my_project
STEP 3. Don't forget to go into that project and set the local rbenv ruby version.
% cd my_project
% rbenv local 1.9.2-p290
Now if you want to delete this project, just delete it as normal.
If you want to delete / manage a rails version from rbenv gems, you can use regular gem commands, just prefix your command line with:
% RBENV_VERSION=1.9.2-p290 rbenv exec gem {some command}
And of course, you can delete a complete ruby version and all its shims, etc that are managed within rbenv pretty easily. I like how self contained everything is.
Hope this helps.
For reference, this is a pretty good walk through of at least some of this stuff:
http://ascarter.net/2011/09/25/modern-ruby-development.html
There is a rbenv plugin called rbenv-gemset which should behave similar to the rvm gemset-command but since rbenv was never intended to work this way, I haven't tried it.
I usually manage Rails versions with Bundler as Nathan suggested in the comments of one of the other answers. I create a Gemfile with my desired Rails version, run bundle install, create the Rails application, let it replace the Gemfile and let Bundler take over:
mkdir my-rails-app
cd my-rails-app
echo "source 'https://rubygems.org'" > Gemfile
echo "gem 'rails', '3.2.17'" >> Gemfile
bundle install
bundle exec rails new . --force --skip-bundle
bundle update
If you want more detail, I wrote an article on my blog about it.
Hope it helps!
If you have setup ruby using rbenv the following will work.
Installing rails, the latest version (7.x as of Oct 2022)
gem install rails -v 7.0.2.4
# Find exe
rbenv rehash
To create a rails project with the latest rails version,
rails new project_1
This will create a rails application with the latest version, to verify we can see the rails version in the Gemspec file (or) see the logs during the installation,
Installing rails, 6.x.x.x version
Assuming we are going to install rails 6.0.4.8, then issue the following commands
gem install rails -v 6.0.4.8
rbenv rehash
Now, to create a rails project with 6.0.4.8 version (which is installed previously), specify the rails version along with the rails command.
rails _6.0.4.8_ new project_2
This will create a rails application with the 6.x version, to verify we can see the rails version in the Gemspec file (or) see the logs during the installation,
Other notes
Similarly, we can manage any no of rails versions in any number of
projects.
rbenv rehash Installs shims for all Ruby executables known to
rbenv
In this approach, you don't need to set or modify any ruby
environment variables.
You don't need to modify Gemspec file by yourself.
The instructions work as of Oct 2022.