Apply the same code on PHP to content of component and each module

Question

I have some code on PHP something like:

$oldstring = ...;
...
$pattern = ...;
$newstring = preg_replace_callback($pattern, ... {...}, $oldstring);

echo $newstring;

I need to apply this code (maybe as class or somehow) to content of component and each existing module on the page, something like:

$doc = JFactory::getDocument();

$oldcomponent = $doc->getBuffer('component', '', array('class'=> ''));
// the same code for applying
echo $newcomponent;

$oldmodule1 = $doc->getBuffer('modules', 'position-1', array('style'=> ''));
// the same code for applying
echo $newmodule1;

$oldmodule2 = $doc->getBuffer('modules', 'position-2', array('style'=> ''));
// the same code for applying
echo $newmodule2;

...

$oldmoduleN = $doc->getBuffer('modules', 'position-N', array('style'=> ''));
// the same code for applying
echo $newmoduleN;

The second code is only something like what I mean. I.e. as old strings should be component and each module and they should be echoed as new strings on its positions on the page.

Can someone write example how to create simple Joomla plugin for this purpose. Thanks

Answer 1

There are a variety of ways on how to modify Joomla content with a plugin:

• A component may call the plugin mechanism, for example com_content uses the "onContentPrepare" event. You can use this to modify com_content content. The plugins for this are in plugins/content, but that is just common behaviour, the plugin would work in any folder.

• A system plugin can take the output of any component and modify it, for example with regular expressions.

• A system plugin can also modify the whole HTML

• A module calls the "onRenderModule" event, so you can use this to modify the module output.

So you need to create a plugin for components and one for modules and you can share your code, for example by installing a library.

A more detailed example:

• You can see in https://github.com/joomla/joomla-cms/blob/staging/libraries/cms/module/helper.php, line 235 how onRenderModule is called with $module and $attribs
• $module contains the data stored in the module table $attribs is an array which contains 'name' -> position of the module and 'style' -> the module Chrome used.

So putting it all together:

public function onRenderModule($module, $attribs)
{
    $modulePosition = $attribs['name']
    $moduleStyle = $attribs['style']

    $module->content = str_replace('foo','bar',$module->content;

}

This would replace all occurences of foo with bar in any module.

Answer 2

Ok, I've found out how to modify component and any module with a system plugin:

class PlgSystemSomename extends JPlugin
{
    public function onAfterDispatch()
    {
        $doc = JFactory::getDocument();
        $oldComponent = $doc->getBuffer('component');
        $db = JFactory::getDBO();
        $query = $db->getQuery(true);
        $query->select($db->quoteName('position'))
            ->from($db->quoteName('#__modules'))
            ->where($db->quoteName('published')." = 1 AND ".$db->quoteName('client_id')." = 0");
        $db->setQuery($query);
        $list = $db->loadObjectList();
        ...
        $pattern = ...;
        $newComponent = preg_replace_callback($pattern, ... {...}, $oldComponent);
        if(count($list) > 0) {
            foreach($list as $module) {
                $newModule = preg_replace_callback($pattern, ... {...}, $doc->getBuffer('modules', $module->position, array('style'=> 'xhtml')));
                $doc->setBuffer($newModule, 'modules', $module->position, array('style'=> 'xhtml'));
            }
        }

        $doc->setBuffer($newComponent, 'component');
        return true;
    }
}