Magento product filter collection

Question

I am developing a project with custom module of my own.There is a situation i want to filter all the products of the store with my custom logic having data provided by each user from the cookie.Other products will not be displayed in any part of the website to the same user.Whether it is related products block or from any slider etc.Which model should i overwrite in order to filter default product collection ?

Answer 1

if you need to apply your own filtering in all product collection, then the best way would be listen to the event catalog_product_collection_load_before. This event will called in every product load operation.

In your module, first you need to setup this event. So add this content inside your module's config.xml

File : app/code/local/Namespace/Modulename/etc/config.xml

<config>
   <frontend>
        <events>
            <catalog_product_collection_load_before>
                <observers>
                    <namespace_modulename>
                        <type>singleton</type>
                        <class>Namespace_Modulename_Model_Observer</class>
                        <method>applyCustomFilter</method>
                    </namespace_modulename>
                </observers>
            </catalog_product_collection_load_before>
        </events>
    </frontend>
    <global>
        <models>
            <namespace_modulename>
               <class>Namespace_Modulename_Model</class>
            </namespace_modulename>
        </models>
    </global>
</config>

Now define your observer class like this

File : app/code/local/Namespace/Modulename/Model/Oberver.php

<?php
class Namespace_Modulename_Model_Observer
{
     public function applyCustomFilter($observer)
     {
            $collection = $observer->getEvent()->getCollection();

            //you got collection above now perform filtering here.
            $collection->addAttributeToFilter(...);

            return $this;
     }
}

Any filtering that you apply inside applyCustomFilter() will then affect every product collections.

Hope that will help you.

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