Deploying a Sinatra app to Heroku

README.md

Deploying a Sinatra app to Heroku

Database

The location of the database Heroku provides can be found in the environment variable DATABASE_URL. Check the configure-block of toodeloo.rb for an example on how to use this.

Server

Heroku is serving your apps with thin, with means you have all your thin goodness available, such as EventMachine.

Rackup file

Heroku can serve all Rack applications. It looks for a rackup file named 'config.ru' in the root directory. Thus serving a Sinatra app is simple:

require 'toodeloo'
run Sinatra::Application

Create app and deploy

The whole process of deploying this small Sinatra app was as follows:

$ git clone git://gist.github.com/68277.git toodeloo $ cd toodeloo $ .. unpack gems and add to git repo .. $ heroku create toodeloo $ git remote add heroku git@heroku.com:toodeloo.git $ git push heroku master

That's it. You can see it in action at http://toodeloo.heroku.com

config.ru

require 'toodeloo'

run Sinatra::Application

Gemfile

source 'http://rubygems.org'
gem 'sinatra'
gem 'dm'

toodeloo.rb

require 'sinatra'
require 'dm-core'

# Heroku has a limited number of gems installed, and chance is that you need
# some additional gems, like haml. The trick is to vendor them with your app. 
# First, add this snippet, which will add vendor/*/lib to your load path:
Dir['vendor/*'].each do |lib|
  $:.unshift(File.join(File.dirname(__FILE__), lib, 'lib'))
end
# Next, unpack all the gems you need in vendor:
#
# $ mkdir vendor
# $ cd vendor/
# $ gem unpack haml
#
# And finally require it (which isn't really necessary in this case, since
# Sinatra does it for you, but for sake of the example we'll do it):
require 'haml'

# Make sure your DataMapper models are defined *before* the configure
# block, otherwise your DB won't be updated and you're in for trouble and
# what-not.
class Todo
  include DataMapper::Resource
  property :id, Integer, :serial => true
  property :text, String
end

configure do
  # Heroku has some valuable information in the environment variables.
  # DATABASE_URL is a complete URL for the Postgres database that Heroku
  # provides for you, something like: postgres://user:password@host/db, which
  # is what DM wants. This is also a convenient check wether we're in production
  # / not.
  DataMapper.setup(:default, (ENV["DATABASE_URL"] || "sqlite3:///#{Dir.pwd}/development.sqlite3"))
  DataMapper.auto_upgrade!
end

get '/' do
  @todos = Todo.all
  haml :index
end

post '/' do
  Todo.create(:text => params['todo'])
  redirect '/'
end

# Inspect the environment for additional information. This should *not* be
# accessible in a production app.
get '/env' do
  content_type 'text/plain'
  ENV.inspect
end

__END__

@@ index
!!!
%html
  %head
    %title Toodeloo
  %body
    %h1 Toodeloo
    %ul
      - @todos.each do |todo|
        %li= todo.text
    %form{:action => '/', :method => 'POST'}
      %input{:type => 'text', :name => 'todo'}
      %input{:type => 'submit', :name => 'Todo!'}
    %a{:href => 'http://gist.github.com/68277'} Read more..