Building Components for J!1.5

As Presented by Steven Pignataro Owner of ‘corePHP’ Web

Development

What do we build for?

• Joomla! 1.5 is built to run on PHP4 and PHP5

• Need to keep this in mind when developing extensions.

• Most developers are dropping support for PHP4 – some are not – you make the choice.

Development Applications

• ‘corePHP’ Developers use Aptana and extended plugins– http://www.aptana.org

• J!Dump – great tool to get a detailed out put for debugging.– http://www.joomlacode.org/gf/project/jdump

Where do we start?

• Joomla! 1.5 has 2 locations that we are going to be developing for:– Joomla! Frontend (public accessible)– Joomla! Backend (admin accessible)

Libraries

• J!1.5 provides a extensive collection of useful libraries that are easily called via jimport:– Jimport(‘joomla.mail.*’);– Jimport(‘joomla.filesystem.file’);

• Open up libraries folder and call by the main folder / sub folder / filename.

• Can be called like this:– Jimport(‘cache.cache’);

How to grab from Request

• Development with PHP Applications require the use of grabbing data from $_GET, $_GET, $_FILES, $_COOKIE, $_REQUEST, etc.

• Joomla! 1.0.x we used mosGetParam(); we now pull from the JRequest function which gives us additional control:– JRequest::setVar()– JRequest::getVar()

JRequest::GetVar()

• How do we use it?– $value = $JRequest::getVar(‘value’, 0);

• Other Methods for getting values:– getInt()– getFloat()– getBool()– getWord()– getCmd()– getString()

• With these get strings we are guaranteeing that the values grabbed will be either an Integer or a String, or any of the other JRequest methods.

JRequest::setVar()

• JReqeust::setVar() methods allows you to set the values into the request.

• Examples of use are:– JRequest::setVar(‘task’, ‘displayData’);

Multilingual Support

• Joomla! allows superior support for UTF-9 (Unicode Transformation Format-8) ecnodting. Available strings are used through JText:– _()

• echo JText::_(‘ARTICLE_COUNT’);

– sprintf() -> equivalent to PHP sprintf()• $value = JText::sprintf(‘ARTICLE # NOT FOUND’, 92);• Language INI file will have:

– ARTICLE # NOT FOUND=Article #%d not found

– printf() -> equivalent to PHP printf()

Database

• The core of Joomla! has two database drivers:– MySQL– MySQLi

• The database can be globalized using JFactory calls:– $db =& JFactory::getDBO();

How to Query the Database

• We use setQuery() method to create the object we want to execute:$db =& Jfactory::getDBO();

$query = ‘SELECT * FROM ‘

. $db->nameQuote(‘#__corephp’)

. ‘ WHERE ‘

. $db->nameQuote(‘firstname’)

. ‘ = ‘

. $db->Quote(‘Steven’)

$db->setQuery($query)

How to receive results

• With Joomla! 1.5 we have similar methods that allow us to grab results from the database. In the next few slides I will briefly discuss each one.

Database Methods

• loadResult(): string

• loadResultArray( numinarray): arrayArray{

[0] => Foo[1] => Bar

}

Database Methods (cont.)• loadAssoc(): array

Array{

[id] => 25[name] => Steven

}• loadAssocList( key: string=‘’): array

Array{

[0] => Array{

[id] => 90[name] => Steven

}

[1] => Array{

[id] => 91[name] => Michael

}}

Database Methods (cont.)• loadObject(): stdClass

stdClass Object{

[id] => 25[name] => Steven

}• loadObjectList( key: string=‘’): array

Array{

[0] => stdClass Object{

[id] => 90[name] => Steven

}

[1] => stdClass Object{

[id] => 91[name] => Michael

}}

Database Methods• loadRow(): array

Array{

[0] => Foo[1] => Bar

}• loadRowList( key: int): array (Example: $db->loadRowList(0));

Array{

[0] => Array{

[id] => 90[name] => Steven

}

[1] => Array {[id] => 91[name] => Michael

}}

JRoute

• Joomla! allows us to take advantage of SEF URI’s – in order to get these we need to use the JRoute::_() method

How do we use JRoute?

• With JRoute you will wrap your links like the following:– Echo JRoute::_(‘index.php?

option=com_penguinpower&cat=1&data=6’);

• With SEF Turned on the above link would possible produce something as follows:– http://www.corephp.com/index.php/component/pengui

npower/1/6/

• Not entirely SEF friendly

Building the Route

• To build the route – you need to create a file called router.php in the root of the component folder.

• Two functions will be abvailable in this file:– BuildRoute()– ParseRoute()– Prefixed prior to above functions is the

component name.

Example of router.php

• function penguinpowerBuildRoute(&$query) {$segments = array();if (isset($query[‘cat’])) {

$segments[] = $query[‘cat’];unset($query[‘cat’];if(isset($query[‘data’])) {

$segments[] = $query[‘data’];unset($query[‘data’]);

}}

return $segments;}

Example Cont.

• Function pengiunpowerParseRoute($segments) {

$query = array();if (isset($segments[0])) {

$query[‘cat’] = $segments[0];if (isset($segments[1])) {

$query[‘data’] = $segments[1];}

}return $query;}

Router.php – the truth

• Some developers are skipping over this and not realizing the benfit this has to there component. By allowing your users to have high quality SEF links - you are allowing your users to have superior power.

• It is important to allow your users to have proper SEF links. JRoute gives this ability and is not difficult to use if you are familiar with the previous methods of SEFing a link.

Errors

• J! 1.5 provides superior error messaging over the previous versions of Joomla! by using the class methods:– JError::raiseError()– JError::raiseWarning()– JError::raiseNotice()

raiseError

• JError::raiseError(‘403’, JText::_(‘You are not a penguin – go back north’));

• Thins will provide a page with an error message with a 403 message. You can also perform other forms of errors such as 500 when an error occurs.

raiseWarning

• JError::raiseWarning(‘ERROR_CODE’, JText::_(‘What makes a penguin fly during a cold night?’));

• This outputs simple messages above the mainBody of the site.

ACL

• Sorry – this is only an hour long – please request further information about ACL and how your site can be improved with ‘corePHP’ Community ACL.

Security

• Remember to start all your files with the following statement (this is one step to security – but do not stop there):– Defined(‘_JEXEC’) or die(‘Penguin Bites’);

SQL Injection

• To ensure your code is secure use the following methods to protect your data:– $db =& JFactory::getDBO();– $data = $db-

>QuotegetEscaped(JRequest(‘data’));

Extension Access Control

• There is a simple and easy way to allow access to copmonents and this can be done by doing the following example:– $acl =& JFactory::getACL();

$acl ->_mos_add_acl(‘com_penguinpower’, ‘manage’, ‘users’, ‘super administrator’);

Redirects

• Using redirects could be used when saving data / copying items / creating a new item / publishing/unpublishing or anything that you might need to redirect the user to a different location

Redirects in use

• $mainframe->direct(‘index.php?option=com_penguinpower’);or

• $mainframe->redirect(‘index.php?option=com_the-zend-penguin’, ‘Why fear the Zend Penguin?’);

What's next?

• Well one there is a massive API – no way it can be covered in one sitting. Recommended reading:

• Mastering Joomla! 1.5 Extension and Framework Developmentby James Kennard