Magento 1. Creating a module. Part 5. Models

Create a model class, resource, and data collection

Magento uses "thin" models. For this, two models are created:

1. The usual model for implementing business logic,
2. Resource model - to interact with the database.

And so, we need to create two models + resource class. The resource class is used to output grid data.

Create a model class

Create a folder:

app/code/local/My/Articles/Model

Adding a file:

app/code/local/My/Articles/Model/Articles.php

Adding the code:

<?php

class My_Articles_Model_Articles extends Mage_Core_Model_Abstract
{
    public function _construct()
    {
        parent::_construct();
        /**
         *   Initializing the model. In the configuration file (see below)
         *   Tag <myarticles> / File Articles.php 
         */
        $this->_init("myarticles/articles");
   }
}

Note that here _construct () is correct, not __construct ()

Adding a Resource Model

Here we implement the removal of the image after the deletion of the record, as well as the output functionality of the path to the picture.

Create a folder:

app/code/local/My/Articles/Model/Resource

Create a file:

app/code/local/My/Articles/Model/Resource/Articles.php

Adding the code:

<?php

class My_Articles_Model_Resource_Articles extends Mage_Core_Model_Mysql4_Abstract
{
    public function _construct()
    {
        /*
            Initialize the resource model.
            In the configuration file (see below)
            Tag    <myarticles> / tag <table_myarticles>
            id - field name with Primary Key
        */
        $this->_init("myarticles/table_myarticles", "id");
    }

    /**
     * Function is called after data is deleted
     * Here we delete the picture file
     * @return Mage_Core_Model_Resource_Db_Abstract
     */
    protected function _afterDelete()
    {
        $helper = Mage::helper('myarticles');
        @unlink($helper->getImagePath($this->getId()));
        return parent::_afterDelete();
    }

    /**
     * The function returns the path to the image
     * We will use our helper for this
     * @return null
     */
    public function getImageUrl()
    {
        $helper = Mage::helper('myarticles');
        if ($this->getId() && file_exists($helper->getImagePath($this->getId()))) {
            return $helper->getImageUrl($this->getId());
        }
        return null;
    }
}

Adding to the configuration file

app/code/local/My/Articles/etc/config.xml

We need to add parameters (see comments)

1. Code for models
2. The code for the model resources

<?xml version="1.0" ?>
<config>
   <modules>
       <My_Articles>
           <version>1.0.0</version>
       </My_Articles>
   </modules>
   <!-- Code for controller -->
   <frontend>
       <routers>
           <marticles>
               <use>standard</use>
               <args>
                   <module>My_Articles</module>
                   <frontName>articles</frontName>
               </args>
           </marticles>
       </routers>
   </frontend>
   <global>
   <!-- Code for models -->
    <models>
        <myarticles>
            <!-- We created a class My_Articles_Model_Articles, in this parameter, we only specify the path to the file My_Articles_Model without the filename Articles -->
            <class>My_Articles_Model</class>
            <resourceModel>myarticles_recource</resourceModel>
        </myarticles>
        <!-- The code for the model resources -->
        <myarticles_recource>
            <class>My_Articles_Model_Resource</class>
            <entities>
                <table_myarticles>
                    <table>my_articles</table>
                </table_myarticles>
            </entities>
        </myarticles_recource>
    </models>
       <!-- Code for adding tables to the database -->
       <resources>
           <marticles_setup>
               <setup>
                   <module>My_Articles</module>
               </setup>
           </marticles_setup>
       </resources>
   </global>
</config>

Creating a model of collections

Resources are used to output a list of data from the model. Resources are used in data grid

Create a folder:

app/code/local/My/Articles/Model/Resource/Articles

Create a file:

app/code/local/My/Articles/Model/Resource/Articles/Collection.php

Adding the code:

<?php

class My_Articles_Model_Resource_Articles_Collection extends Mage_Core_Model_Mysql4_Collection_Abstract
{
    public function _construct()
    {
        parent::_construct();
        /**
         *   Initialize the model collection. In the configuration file
         *   Tag <myarticles> / File Articles.php 
         */
       $this->_init('myarticles/articles');
   }
}

Article Source: https://кодер.укр/записи/magento-1-создание-модуля-часть-5-модели.