How to deploy Ruby Sinatra applications to the Heroku and

Google AppEngine cloud platforms

Ruby and the Cloud

Chang Sau SheongGeekcamp SG22 Aug 2009

Beginner/Intermediate

What I am going to show here

• Use Sinatra to write a TinyURL clone (Snip)• Deploy Snip to Heroku• Deploy Snip to Google AppEngine• Disclaimer – No affiliation with Heroku or

Google, all opinions are my own

Clone TinyURL in 40 lines of Ruby code

URL Shorteners

• First successful one was TinyURL, started in 2002

• Generate a short URL for any URL, going to short URL will redirect to the original

• Usage exploded with popularity of Twitter• Biggest market share today – TinyURL, used to

be default for Twitter, second is bit.ly• Twitter switched to bit.ly early May 2009

Sinatra• Rack-based minimalist Ruby web application

framework

require ‘rubygems’require ‘sinatra’get ‘/hi’ do “Hello Geekcamp!”end

• Designed and developed by Blake Mizerany, financial support by Heroku

http://github.com/sausheong/snip

Some notes

• Base 36 conversion to reduce number of characters used– Ruby provides conversion with to_i and to_s

• DataMapper– ActiveRecord, Sequel also supported– Use DATABASE_URL environment variable

• Embedded view template with use_in_file_templates!

QUESTIONS? (BEFORE CONTINUING)

Deploying Sinatra apps to Heroku

• Ruby cloud platform• Hosted on Amazon’s Elastic Compute Cloud

(EC2) • Fully managed, developer only needs to

deploy, all else taken care of• Full set of command line tools to manage

deployment• Deploy to your own domain or *.heroku.com

NginxNginx

VarnishVarnishCustom made from Erlang

Custom made from Erlang

Your code runs here

Your code runs here

PostgresPostgres

MemcachedMemcached

Architecture

DebianDebian

MRIMRI

Rails, Sinatra etc

Rails, Sinatra etc

ThinThin

Inside each dyno

6 steps to deploy

1. Install Heroku gem

1. Create a Rackup file (config.ru)

6 steps to deploy

3. Create empty git repository, add all files and commit the files

6 steps to deploy

4. Create the Heroku application using the Heroku gem

6 steps to deploy

5. Push code to git repository

6 steps to deploy

6. Go into the Heroku console to create the database

Done!

QUESTIONS? (BEFORE CONTINUING)

Deploying Sinatra apps to Google AppEngine with JRuby

• Lets you run your web applications on Google's infrastructure

• Fully managed, only deploy and runs• Can use own domain name or *.appspot.com• First released April 2008, first language used

Python• April 2009, Java support released

Google App Engine

App Engine for Java

• Java 6 virtual machine (JVM), App Engine SDK supports Java 5 and later

• Servlet classes, JSPs, static files and data files, deployment descriptor (web.xml), configuration files, in a standard WAR directory structure (not WAR file)

• Persistence using DataStore with JDO and JPA• Caching using App Engine’s memcache with JCache• Use Mail service with JavaMail• Image service, Google Accounts for authentication

• JRuby is the Java implementation of the Ruby programming language

• Tightly integrated with Java, able to call Java classes, Ruby 1.8.6 compatible

• Is what we’re going to use to deploy Snip to App Engine

First, some code differences

No base 36 conversion

Using Ola Bini’s Bumble DataStore adapter,Using DataStore key instead of id

http://github.com/sausheong/snip-appengine

What we need to deploy

• JRuby 1.3 RC1 (at least)– Need to split into 2 files because of App Engine’s

10MB file size limit

• Google App Engine for Java SDK• Warbler – the JRuby WAR packager– Includes JRuby-Rack

Steps to deploy

1. Install necessary gems (remember to use JRuby and not C Ruby)

2. Create a config directory and create the Warbler configuration

Steps to deploy

3. Replace it with this file

This is important – your app name

We can’t use the default full JRuby library it is too large forGAE/J – max 10MB

Steps to deploy

4. Create a lib folder and add the following library files:• App Engine Java library - appengine-api-1.0-sdk-

1.2.0.jar• Split jruby-complete-1.3.0RC1.jar to:

- jruby-core-1.3.0RC1.jar and - jruby-stdlib-1.3.0RC1.jar

• (JRuby-Rack will be added by Warbler later)5. Create an appengine-web.xml deployment

configuration file

Steps to deploy

Remember this? Your app name before

You might want to do this for debugging

Steps to deploy

6. Create a Rackup configuration file config.ru

Preparation complete!

Steps to deploy

7. Generate the war file and directory using Warble

Steps to deploy

• Output:

Steps to deploy

8. Go into Sinatra code at tmp/war/WEB-INF/gems/gems/sinatra-0.9.1.1/lib/sinatra.

rb and remove use_in_file_templates!

Steps to deploy

9. Deploy to App Engine!

Steps to deploy

QUESTIONS?

http://tinyclone.saush.com

sausheong@gmail.comhttp://blog.saush.comhttp://github.com/sausheong