Subscribing on events in Magento custom models

To subscribe on events only for your custom models in Magento you need to redefine $_eventPrefix property of your model like this:

<?php

class Vendor_Module_Model_Something extends Mage_Core_Model_Abstract
{
    protected $_eventPrefix = 'custom_event_prefix';
    
    ...
}

Then you can subscribe on your events in etc/config.xml file of your module as usual:

<?xml version="1.0"?>
<config>
    
    ...

    <global>

    ...

        <events>
            <custom_event_prefix_save_after>
                <observers>
                    <your_identifier>
                        <class>Vendor_Module_Model_Observer</class>
                        <method>yourMethodName</method>
                    </your_identifier>
                </observers>
            </custom_event_prefix_save_after>
        </events>
        
    ...

    </global>

...

</config>

What model events are available?

Here is a list of available events for a model in Magento 1.9 (assuming PREFIX will be replaced by your prefix):

PREFIX_load_before
PREFIX_load_after
PREFIX_save_commit_after
PREFIX_save_before
PREFIX_save_after
PREFIX_delete_before
PREFIX_delete_after
PREFIX_delete_commit_after
PREFIX_clear

Explanation of some:

• PREFIX_save_commit_after this event happens after save transaction commit in resource model
• PREFIX_delete_commit_after happens after delete transaction commit in resource model
• PREFIX_clear happens before clearing data in model’s clearInstance() method. Rarely used

Other events are pretty obvious.

What about standard models?

Magento standard models already have their own event prefixes. If you need them, just do a search for $_eventPrefix = in app/code/core/Mage folder.