Setup Script throws Error : Call to undefined method Mage_Core_Model_Resource_Setup::addAttribute()

Question

I am following a tutorial from the book of Roman Zenner & Vinai Kopp called "Magento - The Handbook for Developers" (german: Magento - Das Handbuch für Entwickler).

Snippet from config.xml

<config>
    <modules>
        <WR_EPO>
            <version>1.0.0.12</version>
        </WR_EPO>
    </modules>
    <global>
        <resources>
            <wr_epo_setup>
                <setup>
                    <module>WR_EPO</module>
                </setup>
            </wr_epo_setup>
            ...

It says that I need this setup script: The script is in (app/code/local/WR/EPO/sql/wr_epo_setup/upgrade-1.0.0.11-1.0.0.12):

<?php
/**
 * @var Mage_Sales_Model_Mysql4_Setup $installer
 */

$installer = $this;
$installer->startSetup();

Mage::Log("Setup Script is getting executed.", 7, "setup.log");

$installer->addAttribute('quote_item', 'shipping_surcharge', array(
        'label' => 'Versandkostenaufpreis'
        ,'type' => 'decimal'
    )
);

$installer->endSetup();

But I get a 500 Status Code Error and the error Call to undefined method Mage_Core_Model_Resource_Setup::addAttribute() is getting logged.

---

I also tried this:

Snippet from config.xml

<config>
    <modules>
        <WR_EPO>
            <version>1.0.0.12</version>
        </WR_EPO>
    </modules>
    <global>
        <resources>
            <wr_epo_setup>
                <setup>
                    <module>WR_EPO</module>
                </setup>
            </wr_epo_setup>
            <wr_epo_sales_setup>
                <setup>
                    <module>WR_EPO</module>
                    <class>Mage_Sales_Model_Mysql4_Setup</class>
                </setup>
            </wr_epo_sales_setup>
            ...

... and moved the setup script from app/code/local/WR/EPO/sql/wr_epo_setup/upgrade-1.0.0.11-1.0.0.12 to app/code/local/WR/EPO/sql/wr_epo_sales_setup/upgrade-1.0.0.11-1.0.0.12 but now the setup script is not getting executed at all, I already removed the entry in the core_resources table and reloaded the site.

Is the tutorial outdated? How to do it right?

Answer 1

The issue isn't with your setup script. You aren't using the proper setup resource in your config.xml.

You need to use the Mage_Sales_Model_Resource_Setup model, not the default setup model.

Example from Magento Sales module:

<config>
    <modules>
        <Mage_Sales>
            <version>1.0.0</version>
        </Mage_Sales>
    </modules>
    <global>
        <resources>
            <sales_setup>
                <setup>
                    <module>Mage_Sales</module>
                    <class>Mage_Sales_Model_Resource_Setup</class>
                </setup>
            </sales_setup>
        </resources>
    </global>
</config>