1. INTRODUCTION TO GROOVY
AND GRAILS AT TAULIA
2012-07-11 for TechTalks.ph
Philip Stehlik

2. About
• Entrepreneur living in San Francisco
• Co-Founder and CTO Taulia
• Coding since teenage years (PHP, Objective-
C, ABAP, JS, Java, Groovy)
• Taulia serving Fortune 2000 companies with
financial software (SaaS + Add-On for SAP)
• Engineering team of ~20 people
• Almost everything in Groovy

3. Taulia's tech stack
• Groovy and Grails from day 1 (Grails 1.0)
• Completely in the cloud
• Integrating with many outside systems
• Partners (e-invoicing, orders, payment
details, ...)
• Web Services
• Interfacing with 'Legacy' technologies
• Gradle, Spring, Hibernate, Jersey, Maven, ...

4. How to interact with our systems
• Browser
• REST
• SOAP
• XMLRPC
• File exchange (FTP(S), AS2, SSH)
• Lots of data munching and transformation

5. Kinds of data
• Invoices, Payment history, Orders
• Vendor data – address, social security, tax ID
• Messages, logins, users
• Logs
• Complete history of 2 yrs of our customers
upon project launch

7. Why we like Groovy
• Simple, nice language
• Dynamic features (for builders, testing, ...)
• Closures
• Tight and easy integration possibilities with
Java
• Open source (Apache 2 license)
• Grails

8. Groovy
• Started development in 2003
• Groovy 1.0 January 2, 2007
• Dynamic language for the Java Virtual
Machine

9. Groovy
• Almost all valid Java code is valid Groovy
code
• Mostly dynamic typing (static typing since 2.0
in core)
• Closures
• DSLs and builders
• Object oriented
• Also 'scripting language'

10. System.out.println("Hello, // optional semicolon
World!"); // System.out, brackets,
println 'Hello, World!' // main(), class defn
// dynamic typing
def name = 'Luke' // GString
println "$name, I am your father."
String yodaSays = """${name}, your // multi-line string
father he is.""" // with static typing
// BigDecimal equals()
assert 0.5 == 1/2
def printSize(obj) { // optional duck typing
print obj?.size() // safe dereferencing
} // native list syntax
def letters = ['a', 'b', 'c'] // closure support
letters.each { letter -> // overload '<' on String
// or: for (pet in pets)
assert letter < 'd'
}

11. Java
for(int x = 0; x < 20; x++){
System.out.println("counter is: "
+ x );
}
Groovy
20.times {
println "counter is: ${it}"
}

12. Running .groovy files
• from command line groovy [file name]
• compile and distribute as JAR/WAR
• groovyConsole
• online http://groovyconsole.appspot.com/
• groovy sh

13. Code

15. Grails
• High productivity web development
framework
• First version in 2006 (1.0 in 2008)
• Version 2.1 recently released
• Open source (Apache 2 license)
• Supported by SpringSource (VMware)

16. Grails
• Spring, Hibernate, Groovy
• MVC
• GroovyServerPages
• Convention over configuration
• Plugin system
o MongoDB, Redis
o Jquery, Mootols, Bootstrap, BlueprintCSS
o Quartz, Apache Shiro, GoogleAppEngine
o ...

17. Code

18. Additional info
• IDE
o IntelliJ
o STS (SpringSource Tool Suite)
o Eclipse plugin
• Other prominent users
o Netflix (Just released Asgard)
o Sky.com
o wired.com
o ...

19. More?

20. Taulia Architecture
• Everything running on AWS
• Multiple zones and regions
• Tomcat
• Apache
• HAProxy
• MySQL, MongoDB, S3
• All traffic and business data encrypted with at
least AES256
• Multiple Grails apps, Servlets, jobs

21. Idea to Deployment
• One-Pager
• Product team:
o Product Manager
o Engineer
o Quality Engineer
Meeting at least weekly with everybody involved to
gauge progress.
• Paper prototyping, interviews, refining
• Everybody involved from the beginning

22. Idea to Deployment #2
• Developer codes locally
• All tests on each commit (Jenkins)
• Auto deploys to integration environment (also
publicly accessible for feedback and demos)
• QE and product feedback
• Iterate
• Two week sprints – deploy to public QA and
PRD
• Using sleeping features

23. Thanks!
Say hi when you are in San Francisco!
p@pstehlik.com
@pstehlik
http://pstehlik.com