Locally Packaging Gem Dependencies for Ruby Applications in Elastic Beanstalk
Today’s guest post is by Charlie Crawford, a developer on the Elastic Beanstalk team.
The Puma Ruby 2 container has a built-in feature to detect locally installed gems. This feature is easy to use, ensures that your production environment is using the same gems as your development environment, and helps your application deploy faster.
Although this feature works for any Ruby application containing a Gemfile, this brief tutorial will cover the concept of a Rails application.
Here is an example of a fairly typical Rails Gemfile:
gem 'rails', '4.1.0' gem 'sqlite3' gem 'sass-rails', '~> 4.0.3' gem 'uglifier', '>= 1.3.0' gem 'coffee-rails', '~> 4.0.0' gem 'jquery-rails' gem 'turbolinks' gem 'jbuilder', '~> 2.0' gem 'sdoc', '~> 0.4.0', group: :doc gem 'spring', group: :development
From the root directory of your application bundle, run this command:
$> bundle package
You will now see a new directory called
vendor/cache in your root directory.
Use the following command to see the contents of the directory. You should see a list like the following.
$> ls vendor/cache actionmailer-4.1.0.gem arel-126.96.36.19940414130214.gem execjs-2.0.2.gem mail-2.5.4.gem rack-test-0.6.2.gem sass-rails-4.0.3.gem thor-0.19.1.gem uglifier-2.5.0.gem actionpack-4.1.0.gem builder-3.2.2.gem hike-1.2.3.gem mime-types-1.25.1.gem rails-4.1.0.gem sdoc-0.4.0.gem thread_safe-0.3.3.gem actionview-4.1.0.gem coffee-rails-4.0.1.gem i18n-0.6.9.gem minitest-5.3.3.gem railties-4.1.0.gem spring-1.1.2.gem tilt-1.4.1.gem activemodel-4.1.0.gem coffee-script-2.2.0.gem jbuilder-2.0.6.gem multi_json-1.9.3.gem rake-10.3.1.gem sprockets-2.11.0.gem treetop-1.4.15.gem activerecord-4.1.0.gem coffee-script-source-1.7.0.gem jquery-rails-3.1.0.gem polyglot-0.3.4.gem rdoc-4.1.1.gem sprockets-rails-2.1.3.gem turbolinks-2.2.2.gem activesupport-4.1.0.gem erubis-2.7.0.gem json-1.8.1.gem rack-1.5.2.gem sass-3.2.19.gem sqlite3-1.3.9.gem tzinfo-1.1.0.gem
Now when you deploy your application with the Puma Ruby 2 container, your environment will automatically use these locally saved gems and will not attempt to download them.
If you want to deploy your app using the online web console, your next step is to create a
.zip of everything in the root directory of your app. This includes the newly created vendor/cache directory.
You can then deploy this
.zip folder using the AWS Elastic Beanstalk console: Elastic Beanstalk Console
You can deploy your cached gems using the eb command-line tool:
$> git add vendor/cache && git commit -m 'Add cached gmes' && git aws.push
For additional help on deploying your finished application, go here: Deploying AWS Elastic Beanstalk Applications in Ruby Using Eb and Git