Refactoring in PHP While Going Open
Source
A Case Study ..
OXID eSales AG
Berlin, 26. June 2009
Erik Kort
Chief Software Architect
© 2009 OXID eSales

OXID eSales AG
 eCommerce Software… nothing else!
 Located in Freiburg, Halle and Kaunas (Lithuania)
 50+ employees… more than half PHP-Developers
© 2009 OXID eSales

About Me
Key facts
OXID eSales AG Chief Software Architect
15+ Years of experience in Software Development
Wide field:
– from Petrochemical industries to eCommerce
– From mobile devices to large servers
Passion: Architecture and Object Oriented Design
© 2009 OXID eSales

OXID eShop 4 Open Source
what does this exactly mean?
OXID eShop Professional Edition is available also as OXID eShop
Community Edition
Licensed under GPLv3
© 2009 OXID eSales

The Past
© 2009 OXID eSales

© 2009 OXID eSales

© 2009 OXID eSales

eShop Extensions
 Module snap in
 Multiple inheritance possible
 Best prepared for extension due to small and atomic functions
 Prepared for multilanguage EN
usage
DE ES
© 2009 OXID eSales

Connecting OXID eShop
 Various connectors to ERP already exist
– Microsoft Dynamics NAV
– Büroware
– SAP
– Generic SOAP interface
– Generic CSV interface
– and many more
 Also connectors to various CRM systems exist
– Drupal
– Typo3
– and many more
 350+ third party extensions in existence
© 2009 OXID eSales

Time to change
© 2009 OXID eSales

XP – eXtreme Programming
© 2009 OXID eSales

eXtreme Programming in OXID
 Iteration length: 1 week
 Only useful elements of XP are taken (e.g. pair programming only if
needed/wanted)
 Iteration planning at the beginning of each week
 Change of plans possible every time – even late in development
process
 Monitoring release by using burndown charts
 Team velocity is constant
 Leads to predictable schedules
– Release dates are fixed in advance and kept
© 2009 OXID eSales

Doing the XP - Goals
 Porting to PHP 5
 Common code base
 Significantly improve quality of source code
 Remove „Big Ball of Mudd“ elements
 Reduce release efforts
 Automatic build system
 Measure code quality (code metrics)
© 2009 OXID eSales

Tools
© 2009 OXID eSales

Risks …
© 2009 OXID eSales

Lessons learned
© 2009 OXID eSales

Psychology ! – „the Gap“
© 2009 OXID eSales

Narural Cleaner Architecture
 Model-View-Controller pattern (MVC)
© 2009 OXID eSales

Results
© 2009 OXID eSales

Memory consumption CE/PE
© 2009 OXID eSales

Memory consumption EE
© 2009 OXID eSales

Response Time CE/PE
© 2009 OXID eSales

Load
 Scales well under high load
© 2009 OXID eSales

Performance under load
© 2009 OXID eSales

Unit tests
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Source Code dispersion
© 2009 OXID eSales

Code coverage
© 2009 OXID eSales

Cyclomatic Complexity
© 2009 OXID eSales

Conclusion
If you are not developing with an agile methodology today, be warned.
It is not about deciding if you want it or not, only about when
© 2009 OXID eSales

Questions?
© 2009 OXID eSales

Press comments
„Der OXID eShop bringt von Haus aus alle für einen
Online-Shop wichtigen Features mit: SEO URLs,
Crossselling, Produktvarianten, beliebig verschachtelbare
Kategorien, Mehrsprachigkeit, Web 2.0 Features etc.“
„Wer ein flexibles Shop-System für höchste Ansprüche
sucht, sollte sich den OXID eShop genauer ansehen.“
PHP Journal 1/2009
„Der eShop überzeugt durch seinen schlanken
Aufbau mit sehr guter Performance, ohne diese mit
zu wenig Out-Of-The-Box-Funktionen oder
mangelnder Erweiterbarkeit kompensieren zu
müssen.“
t3n, 12/ 2008
Die Software überzeugt v.a. durch Usability auf Shop-
nutzerseite.
ix, 01/2009
© 2009 OXID eSales

Let‘s eCommerce…
together!
Thank‘s for joining me!
Erik Kort (erik.kort@oxid-esales.com)
© 2009 OXID eSales