Magento 1.9 – Implementing a Custom Indexer in an Extension

backendextensionsindexerindexingmagento-1.9

I'm working on adding an additional column to a grid in an existing backend extension. I need to add an indexer to to this extension indexing the health (the amount of sells) of (roughly) the last 3 months. (90 days.) I'm splitting the health per month. (So, a field each for 1-30, 31-60 and 61-90 days ago.)

Having basically zero knowledge of Magento indexers I decided to create a simple featureless extension (a functioning adminhtml page and nothing more) and attempt to implement an indexer on that to learn how indexing works.

I've already looked at a few guides trying to figure out how to do this but none of them have fully functioning examples.

Mexbs: Creating custom Magento Index https://archive.is/rE0oz
AionHill: How to implement extremely fast custom indexing in Magento?
https://archive.is/LMiF6
Magento Stack Exchange: Custom Indexer, Magento way ?
Custom Indexer, Magento way ?
Stack Overflow: Magento – Add index to table column using upgrade
script
https://stackoverflow.com/questions/27009691/magento-add-index-to-table-column-using-upgrade-script

They include code needed to create an indexer without detailing how to implement it.

How would I create an indexer, implement it and use it for this kind of data? What type of index do I need to index this information?

I'm looking for an explanation of Magento indexes and a full implementation. Being able to get an index up and running with this kind of data in either extension works for me.

Best Answer

In order to declare an index you need to add this to config.xml inside the global tag:

    <index>
        <indexer>
            <some_unique_index_name_here>
                <model>[module]/indexer_something</model>
            </some_unique_index_name_here>
        </indexer>
    </index>

The model tag in the code above contains the alias for your indexer model. It's similar to the one you use for Mage::getModel(...).

Then you need to create the class referenced in the model tag above:

//you need to extend Mage_Index_Model_Indexer_Abstract class
class [Namespace]_[Module]_Model_Indexer_Something extends Mage_Index_Model_Indexer_Abstract 
{
    //you need to add the following 2 methods `_registerEvent` and `_processEvent`. Let''s just make them do nothing for now.
    protected function _registerEvent(Mage_Index_Model_Event $event) 
    {
        return $this;
    }
    protected function _processEvent(Mage_Index_Model_Event $event) 
    {
        return $this;
    }
    //this is the index name that shows up in indexes section
    public function getName() 
    {
        return Mage::helper('[module]')->__('Your index name');
    }
    //this is the index description that shows up in indexes section
    public function getDescription() 
    {
        return Mage::helper('[module]')->__('Your index description');
    }
    //magic happens here
    public function reindexAll() 
    {
        //here goes the code you need for reindexing
        return $this;
    }
}

If your index needs to run only from the indexes screen or command line then you are set.
If you need your index to be triggered at different events it gets more complicated.
You need to implement the methods that I left blank above _registerEvent and _processEvent.
But these are really specific depending on your events.
You can take a look at these methods from the core indexers to see what happens.
The flat product indexer for example: https://github.com/OpenMage/magento-mirror/blob/magento-1.9/app/code/core/Mage/Catalog/Model/Product/Indexer/Flat.php

Related Solutions

How to Create a Custom Indexer in Magento 1.9

Following info should be a generic guide line that lead to a basic understanding of the whole indexer thing, so are not a complete 'walkthrough' ... ( if you want to contribute to this answer you are welcome )

There are at least 3 steps required here:

Create an index table and related resource model
Create an Indexer model that implement Mage_Index_Model_Indexer_Abstract
add your indexer to Magento configuration

Suggested documentation:

Probably the best way to dig into this is to give a look at Mage_Catalog_Model_Product_Indexer_Price ( this is one of the easier index implementation ).
This resource, at the moment, looks the best guide to understand the whole process to decide what it is the action that is required.

STEP 1
Just add your index table in the installer, as for any other module table.
Your resource model needs to implement the logic for Reindex All in the reindexAll() method: you would probably process all entities here an extract all data.

STEP 2
_registerEvent(),_processEvent() are the important method here, you will need to dig a bit in the below guide to understand the logic behind them

Basically _registerEvent() add some data to the $event, on the base of the 'event type' and the 'entity type'. This extra data will be used in _processEvent() method.

You will need to implement at least the following methods in your model.

/**
 * Data key for matching result to be saved in
 */
const EVENT_MATCH_RESULT_KEY = 'some_key';

/**
 * Initialize resource model
 *
 */
protected function _construct()
{
    $this->_init('module/resource_model');
}

/**
 * @var  Used by matchEvent()
 * for example if you are processing products ...
 */
protected $_matchedEntities = array(
    Mage_Catalog_Model_Product::ENTITY => array(
        Mage_Index_Model_Event::TYPE_SAVE,
        Mage_Index_Model_Event::TYPE_MASS_ACTION,
        Mage_Index_Model_Event::TYPE_DELETE
    )
);

 /**
 * Get Indexer name
 *
 * @return string
 */
public function getName(){
    return 'My indexer Name';
}

/**
 * Get Indexer description
 *
 * @return string
 */
public function getDescription()
{
    return 'My indexer Description';
}

/**
 * Register indexer required data inside event object
 *
 * @param   Mage_Index_Model_Event $event
 *
 * Register data required by process in event object
 * @param Mage_Index_Model_Event $event
 */
protected function _registerEvent(Mage_Index_Model_Event $event)
{
    $event->addNewData(self::EVENT_MATCH_RESULT_KEY, true);
    $entity = $event->getEntity();
    $dataObj = $event->getDataObject();

    if ($entity == Mage_Catalog_Model_Product::ENTITY) {
        if ($event->getType() == Mage_Index_Model_Event::TYPE_SAVE) {
            $event->addNewData('yourmodule_update_product_id', $dataObj->getId());
        } elseif ($event->getType() == Mage_Index_Model_Event::TYPE_DELETE) {
            $event->addNewData(' yourmodule _delete_product_id', $dataObj->getId());
        } elseif ($event->getType() == Mage_Index_Model_Event::TYPE_MASS_ACTION) {
            $event->addNewData(' yourmodule _mass_action_product_ids', $dataObj->getProductIds());
        }
    }
}

/**
 * Process event based on event state data
 *
 * @param   Mage_Index_Model_Event $event
 */
protected function _processEvent(Mage_Index_Model_Event $event){
    /** DO STUFF **/
    return $this;
}

STEP 3
Add this to your configuration, [module/model] is the model created in step 2. So at this point if you go in system->indexer you will see a new entry

<global>
    ......
    <index>
        <indexer>
            <some_key>
                <model>module/model</model>
            </some_key>
        </indexer>
    </index>
    ......
</global>

Sources:

Magento – How to add upgrade SQL lines to extension

There's a great article by Inchoo on installer and updater scripts: http://inchoo.net/magento/magento-install-install-upgrade-data-and-data-upgrade-scripts/

It comes down to adding a new file upgrade-1.0.0-1.1.0.php and chancing the version number in the config.xml from 1.0.0 to 1.1.0

Best Answer

Related Solutions

How to Create a Custom Indexer in Magento 1.9

Magento – How to add upgrade SQL lines to extension

Related Topic