1. How
to
write
Custom
Modules
for
PHP-­based
E-­
Commerce
Systems
Roman
Z.

2. Roman
Zenner
• Working
as
freelance
trainer,
author
and
consultant
since
2004
• Has
written
three
books
on
Magento
and
OXID
eShop
• Is
in
the
process
of
writing
a
“cookbook”
on
OXID
eShop
with
Joscha
Krug
• Publishes
in
various
magazines

3. Initial
thoughts
• Modularity
a
no-­‐brainer
in
today’s
ecommerce
software
• There
must
be
a
way
of
extending
classes
or
an
event-­‐listener
system
in
order
to
integrate
custom
functionalities

4. Types
of
modules
• Encapsulate
graphical
(template)
changes
• Provide
additional
information
(e.g.
for
an
article
• Special
calculations
• Payment
and
shipping
• Other
interfaces
(ImpEx,
etc.)

5. Today‘s
candidates
• Magento
• OXID
eShop
• Shopware

6. http://www.flickr.com/photos/exey/3815327201

8. Brief
History
• First
stable
version
released
in
spring
2008
• Community
Edition
under
OSL
• Professional
and
Enterprise
Editions
• Based
on
Zend
Framework
and
MySQL
• Relies
heavily
on
EAV
structure
• XML
de^initions
• Bought
by
eBay
in
2011
(X.commerce)
• Current
stable
version:
1.7.0.2

9. Structure

10. Templates
(1)

11. Templates
(2)

12. Templates
(2)
<block type="page/html“ name="root" output="toHtml“ template="page/3columns.phtml">
<block type="page/html_header" name="header" as="header">
<block type="page/switch" name="store_language" as="store_language"
template="page/switch/languages.phtml"/></block>
</block>
Template: /layout/page.xml
<?php if(count($this->getStores())>1): ?>
<div class="form-language“>
<?php foreach ($this->getStores() as $_lang): ?>
<?php $_selected = ($_lang->getId() == $this->getCurrentStoreId())
? ' selected="selected"' : '' ?>
<option value="<?php echo $_lang->getCurrentUrl() ?>"<?php echo $_selected ?>>
<?php endforeach; ?>
</div>
<?php endif; ?>
Template: /template/page/switch/languages.phtml

13. Drilling
down
(1)
Example:
How to get from the article name in
the template to the database field?

14. Drilling
down
(2)
1. Block: <block type="catalog/product_view" name="product.info" template="catalog/
product/view.phtml">
2. Template: /app/design/frontend/base/default/template/catalog/product/view.phtml
3. Block class: Mage_Catalog_Block_Product_View
4. Model: Mage_Catalog_Model_Product:
public function getProduct()
{
if (!Mage::registry('product') && $this->getProductId()) {
$product = Mage::getModel('catalog/product')->load($this->getProductId());
Mage::register('product', $product);
}
return Mage::registry('product');
}

15. Drilling
down
(3)
1. Abstract class: Mage_Core_Model_Abstract
2. Resource model: Mage_Core_Model_Mysql4_Abstract
public function load($id, $field=null)
{
$this->_beforeLoad($id, $field);
$this->_getResource()->load($this, $id, $field);
$this->_afterLoad();
$this->setOrigData();
$this->_hasDataChanges = false;
return $this;
}

16. Modules

18. Brief
History
• OS-­‐Edition
since
late
2008.
• Based
on
own
PHP-­‐Framework
&
MySQL
• Recent
version:
4.7.3

19. Features
• ADODB
database
abstraction
layer
• Uses
Smarty
2
(but
Template
Inheritance
by
Smarty
3)
• Block
Inheritance
• Autoloader

20. Structure

21. Template
Inheritance
(1)

22. Template
Inheritance
(2)
[{capture append="oxidBlock_content"}]
[{assign var="oFirstArticle" value=$oView->getFirstArticle()}]
[{/capture}]
[{include file="layout/page.tpl" sidebar="Right"}]
/out/azure/tpl/page/shop/start.tpl

23. Template
Inheritance
(3)
<div id="content">
[{include file="message/errors.tpl"}]
[{foreach from=$oxidBlock_content item="_block"}]
[{$_block}]
[{/foreach}]
</div>
[{include file="layout/footer.tpl"}]
/out/azure/tpl/layout/page.tpl

24. Drilling
down
(1)
Example:
How
to
get
from
the
article
name
in
the
Smarty-­‐Template
to
the
database
^ield?

25. Drilling
down
(2)
• Article
detail
page:
/out/azure/tpl/page/details/inc/productmain.tpl
[{block name="details_productmain_title"}]
<h1 id="productTitle"><span itemprop="name">
[{$oDetailsProduct->oxarticles__oxtitle->value}]
[{$oDetailsProduct->oxarticles__oxvarselect->value}]</span></h1>
[{/block}]
Scheme: [Object name]->[Table name]__[Field name]->value
• View controller: /application/controller/details.php

26. Drilling
down
(3)
public function render()
{
$myConfig = $this->getConfig();
$oProduct = $this->getProduct();
}
public function getProduct()
{
$sOxid = oxConfig::getParameter( 'anid' );
$this->_oProduct = oxNew( 'oxarticle' );
if ( !$this->_oProduct->load( $sOxid ) ) {
...
}
}

27. Drilling
down
(4)
public function load( $oxID)
{
$blRet = parent::load( $oxID);
public function load( $sOXID)
{
//getting at least one field before lazy loading the object
$this->_addField('oxid', 0);
$sSelect = $this->buildSelectString( array( $this->getViewName().".oxid" => $sOXID));
return $this->_isLoaded = $this->assignRecord( $sSelect );
}
/application/models/oxarticle.php
/core/oxbase.php

28. Custom
classes
(1)
• Most
view-­‐
and
core
classes
can
be
overloaded
• Module
are
registered
in
backend
• Object
instantiation
via
oxNew():
core/oxutilsobject.php
oxArticle
my_oxArticle
our_oxArticle
class my_oxArticle extends oxArticle
class our_oxArticle extends my_oxArticle

29. Custom
classes
(2)
• This
procedure
becomes
problematic
when
there
is
more
than
one
new
module
wanting
to
extend
a
speci^ic
class.
• Solution:
oxNew()
dynamically
creates
transparent
classes
in
the
form
of:
[class-­name]_parent
• This
means
that
by
means
of
the
following
structure,
module
classes
can
be
chained:
– oxArticle
=>
my_oxArticle&our_oxArticle

30. Plugins
(1)
• Task:
Write
a
module
that
displays
the
remaining
time
until
X
mas
with
each
article.
1. New
module
directory:
/modules/xmas/
2. Publishing
it
via
metadata.php
(used
to
be
via
Admin)
'extend' => array(
'oxarticle' => ‘xmas/xmasArticle'
)

31. Plugins
(2)
class
xmasArticle
extends
xmasArticle_parent
{
public
function
getDaysLeft()
{
$time
=
mktime(0,
0,
0,
12,
25,
2011,
1)
-­‐
time();
$days
=
^loor($time/86400);
return
$days;
}
}
<div>Only [{$oDetailsProduct->getDaysLeft()}] days left until Xmas!</div>
/modules/xmas/xmasArticle.php
/out/azure/tpl/page/details/inc/productmain.tpl

33. Brief
History
• First
stable
version
released
in
2007.
• OS-­‐Edition
since
October
2010.
• Since
v.3.5
based
on
Enlight
Framework
(based
on
ZF)
&
MySQL
• MVC-­‐Model
• Backend
based
on
ExtJS
4
• Templates
based
on
Smarty
3
• Recent
version:
4.0.7

34. Enlight-­‐Framework
• Basis
functionalities
are
inherited
from
Zend
Framework:
• Syntax
and
Work^low
• Request-­‐
and
Response-­‐Objects
• Action-­‐Controller
Design
• Rewritten
Router
/
Dispatcher
and
View-­‐
Object
optimised
for
performance
and
expandability
• Own
plugin
system
based
on
events
and
hooks

35. Template-­‐Structure

36. index.tpl
{* Content section *}
<div id="content">
<div class="inner”>
{* Content top container *}
{block name="frontend_index_content_top"}{/block}
{* Sidebar left *}
{block name='frontend_index_content_left'}
{include file='frontend/index/left.tpl'}
{/block}
{* Main content *}
{block name='frontend_index_content'}{/block}
{* Sidebar right *}
{block name='frontend_index_content_right'}{/block}
<div class="clear">&nbsp;</div>
</div>
</div>

37. Template-­‐Inheritance
{extends file=”../_default/frontend/home/index.tpl}
{block name=’frontend_index_content’ prepend}
<h1>Hallo Welt</h1>
{/block}
SMARTY:
Append – Prepend - Replace

38. Plugin-­‐Directory
Structure

39. Drilling
down
Example:
How
to
get
from
the
article
name
in
the
Smarty-­‐Template
to
the
database
^ield?

40. Drilling
down
(2)
• Article
detail
page:
templates_defaultfrontenddetailindex.tpl
• Part
that
displays
article
name
in
frontend
• Template-­‐Path
(frontend/detail/index.tpl)
tells
us
where
to
^ind
the
corresponding
controller.
In
this
case:
Shopware/Controllers/
Frontend/Detail.php
–
indexAction.
• Get
article
information
from
Model
and
assign
to
template
• Shopware()-­>Modules()-­>Articles()
is
a
service
locator
to
access
the
main
article
object
that
could
be
found
at
/engine/core/class/
sArticles.php
• sGetArticleById
fetches
a
certain
article
by
id
from
database
and
returns
the
result
as
an
array
for
further
processing

41. Plugins:
Bootstrap
<?php
class Shopware_Plugins_Frontend_IPCDEMO_Bootstrap
extends Shopware_Components_Plugin_Bootstrap
{
public function install()
{
//
return true;
}
public static function onPostDispatch(Enlight_Event_EventArgs $args)
{
// Still empty
}
}

42. Plugins:
Event
public function install()
{
$event = $this->createEvent('Enlight_Controller_Action_PostDispatch','onPostDispatch');
$this-> subscribeEvent($event);
$form = $this->Form();
$form->setElement('textarea', ’yourtext',
array('label'=>’Text for left column’,'value'=>’Hello World'));
$form->save();
return true;
}

43. Plugins:
Listener
!public static function onPostDispatch(Enlight_Event_EventArgs $args)
{
$view = $args->getSubject()->View();
$config = Shopware()->Plugins()->Frontend()->IPCDEMO()->Config();
$view->pluginText = $config->yourtext;
$view->addTemplateDir(dirname(__FILE__)."/Views/");
$view->extendsTemplate('plugin.tpl');
}

44. Plugins:
Hooks
<?php
class Shopware_Plugins_Frontend_myHook_Bootstrap extends Shopware_Components_Plugin_Bootstrap
{
public function install()
{
$hook = $this->createHook(
'sArticles',
'sGetArticleById',
'onArticle',
Enlight_Hook_HookHandler::TypeAfter,
0
);
$this->subscribeHook($hook);
return true;
}
static function onArticle(Enlight_Hook_HookArgs $args)
{
}
}

45. Summary
•
Each
system
employs
a
slightly
different
method
of
inserting
custom
functionalities
•
Layout
and
functional
^iles
are
more
or
less
encapsulated
•
No
core-­‐hacking
required
–
still
a
need
for
testing!

46. Thank
you!
Blog:
romanzenner.com
Skype:
roman_zenner
XING:
xing.com/pro^ile/Roman_Zenner
Twitter:
twitter.com/rzenner

47. MVC-­‐Model
(extended)