Added post about Magento model events

Author: binary-data

_posts/2016-07-14-subscribing-on-events-in-magento-custom-models.md

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+---
+layout: post
+title:  "Subscribing on events in Magento custom models"
+date:   2016-07-14 17:00:00 +0400
+comments: true
+tags: magento magento-models
+---
+To subscribe on events only for your custom models in Magento you need to redefine `$_eventPrefix` property of your model like this:
+
+```php
+<?php
+
+class Vendor_Module_Model_Something extends Mage_Core_Model_Abstract
+{
+    protected $_eventPrefix = 'custom_event_prefix';
+    
+    ...
+}
+```
+
+Then you can subscribe on your events in `etc/config.xml` file of your module as usual:
+
+```xml
+<?xml version="1.0"?>
+<config>
+    
+    ...
+
+    <global>
+
+    ...
+
+        <events>
+            <custom_event_prefix_save_after>
+                <observers>
+                    <your_identifier>
+                        <class>Vendor_Module_Model_Observer</class>
+                        <method>yourMethodName</method>
+                    </your_identifier>
+                </observers>
+            </custom_event_prefix_save_after>
+        </events>
+        
+    ...
+
+    </global>
+
+...
+
+</config>
+```
+
+### What model events are available?
+
+Here is a list of available events for a model in Magento 1.9 (assuming `PREFIX` will be replaced by your prefix):
+
+```
+PREFIX_load_before
+PREFIX_load_after
+PREFIX_save_commit_after
+PREFIX_save_before
+PREFIX_save_after
+PREFIX_delete_before
+PREFIX_delete_after
+PREFIX_delete_commit_after
+PREFIX_clear
+```
+
+Explanation of some:
+
+* **PREFIX_save_commit_after** this event happens after save transaction commit in resource model
+* **PREFIX_delete_commit_after** happens after delete transaction commit in resource model
+* **PREFIX_clear** happens before clearing data in model's `clearInstance()` method. Rarely used
+
+Other events are pretty obvious.
+
+### What about standard models?
+
+Magento standard models already have their own event prefixes. If you need them, just do a search for `$_eventPrefix = ` in `app/code/core/Mage` folder.