Rails Composer
An application template that creates a Rails 3.2 starter app.
It’s the Rails generator on steroids. See the Rails Composer project page.
The Rails Composer application template is built from recipes provided by the rails_apps_composer gem. Need to customize the Rails Composer application template? Want to build your own application template? Use rails_apps_composer.
If you’re new to Rails, see What is Ruby? And Rails?, recommendations for a Rails tutorial, and a list of top resources for Ruby and Rails.
From the RailsApps Project
The RailsApps project provides example applications that developers use as starter apps. Hundreds of developers use the apps, report problems as they arise, and propose solutions. Rails changes frequently; each application is known to work and serves as your personal “reference implementation” so you can stay up to date. Each is accompanied by a tutorial so there is no mystery code. Maintenance and development of the RailsApps applications is supported by subscriptions to the RailsApps tutorials.
Follow on Twitter
Follow the project on Twitter: @rails_apps. Please tweet some praise if you like what you’ve found.
Dependencies
Before running the Rails Composer tool, you need to install:
- The Ruby language (version 1.9.3 or 2.0.0)
- Rails 3.2
Check that appropriate versions of Ruby and Rails are installed in your development environment:
$ ruby -v
$ rails -v
Be sure to read Installing Rails to make sure your development environment is set up properly.
Creating a Starter App
To build a Rails application using the Rails Composer tool:
$ rails new myapp -m https://raw.github.com/RailsApps/rails-composer/master/composer.rb
Replace myapp
with the name of your application.
You can use the -T
flag to skip Test::Unit files or the -O
flag to skip Active Record files:
$ rails new myapp -m https://raw.github.com/RailsApps/rails-composer/master/composer.rb -T -O
Skip Test::Unit if you plan to use RSpec for unit testing. Skip Active Record if you plan to use a NoSQL datastore with an ORM such as Mongoid.
See the “Troubleshooting” section below if you see errors. In general, you’ll avoid many problems if you create your application using RVM as described below.
RVM
Creating a Starter App UsingI recommend using rvm, the Ruby Version Manager, to manage your Rails versions, as described in the Installing Rails article.
Here’s how to generate a new Rails application using the Rails Composer tool and RVM:
$ mkdir myapp $ cd myapp $ rvm use ruby-2.0.0@myapp --ruby-version --create $ gem install rails $ rails new . -m https://raw.github.com/RailsApps/rails-composer/master/composer.rb
You can add the -T
flag to skip Test::Unit files or the -O
flag to skip Active Record files. Skip Test::Unit if you plan to use RSpec for unit testing. Skip Active Record if you plan to use a NoSQL datastore with an ORM such as Mongoid.
Instead of installing Rails into the global gemset and running rails new
, we’ll create a root directory for a new application, create a new gemset, install Rails, and then generate a starter application.
When we create the gemset, the option “—ruby-version” creates .ruby-version and .ruby-gemset files in the root directory. RVM recognizes these files in an application’s root directory and loads the required version of Ruby and the correct gemset whenever you enter the directory.
When we create the gemset, it will be empty (though it inherits use of all the gems in the global gemset). We immediately install Rails. The command gem install rails
installs the most recent stable release of Rails.
Finally we run rails new .
. We use the Unix “dot” convention to refer to the current directory. This assigns the name of the directory to the new application.
This approach is different from the way most beginners are taught to create a Rails application. Our approach makes it easy to create a project-specific gemset to avoid clashes between gem versions when using the Rails Composer tool.
Your Options
The Rails Composer application template will ask you for various preferences, some of which will depend on previous choices.
If you choose “I want to build my own application,” you will get a full set of choices.
If you choose one of the RailsApps example applications, you will get fewer choices but you will get an exact copy of a known working example application. See Rails example applications for more information.
Here’s an example:
question Install an example application? 1) I want to build my own application 2) membership/subscription/saas (Stripe or Recurly) 3) rails-prelaunch-signup 4) rails3-bootstrap-devise-cancan 5) rails3-devise-rspec-cucumber 6) rails3-mongoid-devise 7) rails3-mongoid-omniauth 8) rails3-subdomains question Web server for development? 1) WEBrick (default) 2) Thin 3) Unicorn 4) Puma question Web server for production? 1) Same as development 2) Thin 3) Unicorn 4) Puma question Database used in development? 1) SQLite 2) PostgreSQL 3) MySQL 4) MongoDB question Template engine? 1) ERB 2) Haml 3) Slim (experimental) question Unit testing? 1) Test::Unit 2) RSpec question Integration testing? 1) None 2) RSpec with Capybara 3) Cucumber with Capybara 4) Turnip with Capybara question Fixture replacement? 1) None 2) Factory Girl 3) Machinist question Front-end framework? 1) None 2) Twitter Bootstrap 3) Zurb Foundation 4) Skeleton 5) Just normalize CSS for consistent styling question Twitter Bootstrap version? 1) Twitter Bootstrap (Less) 2) Twitter Bootstrap (Sass) question Add support for sending email? 1) None 2) Gmail 3) SMTP 4) SendGrid 5) Mandrill question Authentication? 1) None 2) Devise 3) OmniAuth question Devise modules? 1) Devise with default modules 2) Devise with Confirmable module 3) Devise with Confirmable and Invitable modules question Authorization? 1) None 2) CanCan with Rolify question Use a form builder gem? 1) None 2) SimpleForm question Install a starter app? 1) None 2) Home Page 3) Home Page, User Accounts 4) Home Page, User Accounts, Admin Dashboard extras Add 'therubyracer' JavaScript runtime (for Linux users without node.js)? (y/n) extras Set a robots.txt file to ban spiders? (y/n) n extras Create a project-specific rvm gemset and .rvmrc? (y/n) n extras Create a GitHub repository? (y/n)
Run the Application
Switch to the application directory to examine and test what you’ve built.
$ cd myapp
Quick Test
For a “smoke test” to see if everything runs, display a list of Rake tasks.
$ rake -T
There’s no need to run bundle exec rake
instead of rake
when you are using rvm (see rvm and bundler integration).
Start the Web Server
If you’ve chosen WEBrick or Thin for your web server, can run the app by entering the command:
$ rails server
To see your application in action, open a browser window and navigate to http://localhost:3000/.
For the Unicorn web server:
$ unicorn
See the app at http://localhost:8080/.
For the Puma web server:
$ rails server puma
See the app at http://localhost:3000/.
Login
If you’ve created a version of the application that sets up a default user, log in with:
- email: [email protected]
- password: changeme
You should delete or change any pre-configured logins before you deploy your application.
Testing
Some versions of the starter application will contain a suite of RSpec unit tests or Cucumber scenarios and step definitions.
After installing the application, run rake -T
to check that rake tasks for RSpec and Cucumber are available.
Run rake spec
to run all RSpec tests.
Run rake cucumber
(or more simply, cucumber
) to run all Cucumber scenarios.
Please send the author a message, create an issue, or submit a pull request if you want to contribute improved RSpec or Cucumber files.
Deployment
For easy deployment, use a “platform as a service” provider such as:
For deployment on Heroku, see the article:
Troubleshooting
Problems? Please check both issues for the Rails Composer tool and the issues for the rails_apps_composer gem.
You should review the article Installing Rails to make sure you’ve updated all the components that are required to run Rails successfully.
Problems with “Could not be loaded… You have already activated…”
If you get an error like this:
Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed. composer Running 'after bundler' callbacks. The template [...] could not be loaded. Error: You have already activated ..., but your Gemfile requires .... Using bundle exec may solve this.
It’s due to conflicting gem versions. See the article Rails Error: “You have already activated (…)”.
Problems with “Certificate Verify Failed”
Are you getting an error “OpenSSL certificate verify failed” when you try to generate a new Rails app from an application template? See suggestions to resolve the error Certificate Verify Failed.
Problems with “Segmentation Fault”
If you get a “segfault” when you try rails new
, try removing and reinstalling rvm.
Application Template Default
The rails new
command creates a new Rails application. If you want to use the Rails Composer application template for every Rails application you build, you can set options for the rails new
command in a .railsrc file in your home directory. Here’s how to set up a .railsrc file to use the template when you create a new Rails application:
# ~/.railsrc -m https://raw.github.com/RailsApps/rails-composer/master/composer.rb
Documentation and Support
The Rails Composer application template is assembled from recipes supplied by the rails_apps_composer gem. See the rails_apps_composer project to understand how the Rails Composer application works.
Customizing the Template
If you wish to change the template to generate an app with your own customized options, you can copy and edit the template file. However, it is better to use the rails_apps_composer gem to create a new application template. You’ll find newer versions of the recipes that make up the application template. You may find issues have been identified and (perhaps) fixed. And it will be easier to maintain your application template if you work from the rails_apps_composer gem.
Writing Recipes
To understand the code in these templates, take a look at Thor::Actions. Your recipes can use any methods provided by Thor::Actions or Rails::Generators::Actions. A big thanks to Yehuda Katz for creating Thor.
About Rails Application Templates
Cooking Up A Custom Rails 3 Template (11 Oct 2010) by Andrea Singh
Rails Application Templates (16 Sept 2010) by Collin Schaafsma
Application templates in Rails 3 (18 Sept 2009) by Ben Scofield
Railscasts: App Templates in Rails 2.3 (9 Feb 2009) by Ryan Bates
Rails templates (4 Dec 2008) by Pratik Naik
Similar Projects
There are many similar projects:
Issues
Problems? Please check both issues for the Rails Composer tool and the issues for the rails_apps_composer gem.
Where to Get Help
Your best source for help with problems is Stack Overflow. Your issue may have been encountered and addressed by others.
You can also try Rails Hotline, a free telephone hotline for Rails help staffed by volunteers.
Contributing
Please make changes to the rails_apps_composer gem rather than changing the Rails Composer application template.
Credits
Daniel Kehoe initiated the RailsApps project and created the Rails Composer application template.
Is it useful to you? Follow the project on Twitter:
@rails_apps
and tweet some praise. I’d love to know you were helped out by what I’ve put together.
License
Copyright 2012 Daniel Kehoe