README.rdoc

Rails 2.3.10 on App Engine (TinyDS)¶ ↑

Do not use rvm (or install and run from JRuby). The google-appengine gem must install into your system MRI. The appengine-sdk gem includes a complete Java app server. We bootstrap Java from MRI, then your app runs inside a servlet container (with access to all the APIs) using the version of JRuby installed into each app.

We assumed Rails 2 would never work without rubygems, and we committed to gem bunlder for JRuby on App Engine, so we were waiting for Rails 3. Fortunately, Takeru Sasaki was able to patch the Rails 2.3.x calls to rubygems, and now we have it working. Rails 2.3.x currently spins up several seconds faster than Rails 3, and just a few seconds behind Sinatra.

See the DataMapper version also: gist.github.com/671792

Install the Development Environment¶ ↑

One meta-gem provides the development environment

sudo gem install google-appengine

Install Rails 2.3.10 with required patches¶ ↑

Install some gems you’ll need

sudo gem install rails -v "2.3.10"
sudo gem install rails_tiny_ds
sudo gem install activerecord-nulldb-adapter

Create a folder for your app

mkdir rails_app; cd rails_app

Download and run the setup script

curl -O http://appengine-jruby.googlecode.com/hg/demos/rails2/rails2310_appengine.rb
ruby rails239_appengine.rb tiny_ds

Working with Your Rails App¶ ↑

Start development server

./script/server.sh

Open local console

./script/console.sh

Publish to production

./script/publish.sh

Support for generators¶ ↑

We disable rubygems in the development environment, and the generators from Rails 2 perform various Gem dependency checks that are too difficult to patch, so we run the generators from the MRI. We also use Josh Moore’s rails_dm_datastore integration plugin.

Generate a restful controller and add it to config/routes.rb

./script/generate scaffold article title:string summary:text url:string \
pages:integer -f --skip-migration

Generate a model for TinyDS

./script/generate td_model article title:string summary:text url:string \
pages:integer -f

You’ve created a RESTful controller, and a TinyDS model

article.rb

class Article < TinyDS::Base
  property :title,      :string
  property :summary,    :text
  property :url,        :string
  property :pages,      :integer
  property :created_at, :time
  property :updated_at, :time
end