Magento – Fatal error: Cannot instantiate interface in Magento 2

interfacemagento2object-manager

As the part of creating bundle product programmatically in Magento 2.
I am getting below error. Even i removed var/cache and generation.

This may be a duplicate question but none of the answer is working for this issue.

Fatal error: Cannot instantiate interface
Magento\Catalog\Api\Data\ProductExtensionInterface in
\ObjectManager\Factory\Dynamic\Developer.php on line 73

Used below code as the reference of link

$productExtension = $objectManager->create(\Magento\Catalog\Api\Data\ProductExtensionInterface::class);
$option = $objectManager->create(\Magento\Bundle\Api\Data\OptionInterface::class);
$option->setTitle('Size');
$option->setType('radio');
$option->setRequired(true);
$option->setPosition(1);
//$option->setProductLinks($links);
$productExtension->setBundleOptions([$option]);
$_product->setExtensionAttributes($productExtension);

I am using object manager for temporary/quick purpose, will convert the object manager to constructor injunction.

Any one can help me on this issue.

Best Answer

I think you have not mentioned the preference in your di.xml. I also faced the same issue when I was creating custom config xml file module.

I got the issue when I called this code:

$testConfig = $this->_objectManager->get('Training\Test\Model\Config\ConfigInterface');
$myNodeInfo = $testConfig->getMyNodeInfo();

Below is the sample code I have added in my di.xml, may be it may help you to get reference:

<preference for="Training\Test\Model\Config\ConfigInterface" type="Training\Test\Model\Config" />

Here I have implemented the interface in Training\Test\Model\Config class and my getMyNodeInfo() method is defined in that Model.

So based on the the preference defined in di.xml the code ->get('Training\Test\Model\Config\ConfigInterface'); will create an object of type Training\Test\Model\Config.

Related Solutions

Magento – Fatal error: Cannot instantiate interface

If you use redis, run:

redis-cli flushall

If you also use an environment like ansible (lxc - server), you'll need to do that command in container. Plus I did the following:

Clear var/generation (or generated/* in newer versions)
Clear var/cache
Check if the module generating the error is enabled and enable it (bin/magento module:enagle Some_Module) or Enable all Magento modules: bin/magento module:enable --all
Compile DI bin/magento setup:di:compile

Magento2 – How to Get Module Version Outside of the Setup Directory

Try \Magento\Framework\Module\ResourceInterface::getDbVersion('Module_Key').

And use a backend model, rather than a frontend model/input renderer.

Like so:

<?php

namespace SalesIgniter\Rental\Model\Config;

/**
 * Config backend model for version display.
 */
class Version extends \Magento\Framework\App\Config\Value
{
    /**
     * @var \Magento\Framework\Module\ResourceInterface
     */
    protected $moduleResource;

    /**
     * @param \Magento\Framework\Model\Context $context
     * @param \Magento\Framework\Registry $registry
     * @param \Magento\Framework\App\Config\ScopeConfigInterface $config
     * @param \Magento\Framework\App\Cache\TypeListInterface $cacheTypeList
     * @param \Magento\Framework\Module\ResourceInterface $moduleResource
     * @param \Magento\Framework\Model\ResourceModel\AbstractResource $resource
     * @param \Magento\Framework\Data\Collection\AbstractDb $resourceCollection
     * @param array $data
     */
    public function __construct(
        \Magento\Framework\Model\Context $context,
        \Magento\Framework\Registry $registry,
        \Magento\Framework\App\Config\ScopeConfigInterface $config,
        \Magento\Framework\App\Cache\TypeListInterface $cacheTypeList,
        \Magento\Framework\Module\ResourceInterface $moduleResource,
        \Magento\Framework\Model\ResourceModel\AbstractResource $resource = null,
        \Magento\Framework\Data\Collection\AbstractDb $resourceCollection = null,
        array $data = []
    ) {
        $this->moduleResource = $moduleResource;

        parent::__construct(
            $context,
            $registry,
            $config,
            $cacheTypeList,
            $resource,
            $resourceCollection,
            $data
        );
    }

    /**
     * Inject current installed module version as the config value.
     *
     * @return void
     */
    public function afterLoad()
    {
        $version = $this->moduleResource->getDbVersion('SalesIgniter_Rental');

        $this->setValue($version);
    }
}

And your system.xml setting definition will look like:

        <group id="current_version" translate="label" type="text" sortOrder="1" showInDefault="1" showInWebsite="1" showInStore="1">
            <label>Current Version Installed</label>
            <field id="version" translate="label" type="label" sortOrder="1" showInDefault="1" showInWebsite="1" showInStore="1">
                <label>Current Version</label>
                <backend_model>SalesIgniter\Rental\Model\Config\Version</backend_model>
            </field>
        </group>

Best Answer

Related Solutions

Magento – Fatal error: Cannot instantiate interface

Magento2 – How to Get Module Version Outside of the Setup Directory

Related Topic