Magento 2 : How to create an EAV entity module?

Question

I want to create EAV entity module. I refer these below links. I want to do the same in Magento 2.

How to create an EAV entity?

How to do it in Magento 2?

Please help me.

Thanks.

UPDATE:

I can able to save the record in the main table. But, I can't able to store in the eav table.

Eg. : I can able to save in vendorname_modulename_modulename table. But, I can't able to save record in vendorname_modulename_modulename_varchar & vendorname_modulename_modulename_text table.

Answer 1

After understanding your question, Not sure but, it seems like your InstallSchema not create properly with foreign key constraint and you didn't properly assign your attributes name in your ResourceModel file.

Compare this both file with your code.

InstallSchema.php :

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

/**
 * Code standard by : RH
 */
namespace RH\HelloWorld\Setup;

use Magento\Framework\DB\Ddl\Table;
use Magento\Framework\Setup\InstallSchemaInterface;
use Magento\Framework\Setup\ModuleContextInterface;
use Magento\Framework\Setup\SchemaSetupInterface;
use RH\HelloWorld\Setup\EavTablesSetupFactory;
use RH\HelloWorld\Setup\HelloWorldSetup;

class InstallSchema implements InstallSchemaInterface
{
    /**
     * @var EavTablesSetupFactory
     */
    protected $eavTablesSetupFactory;

    /**
     * Init
     *
     * @internal param EavTablesSetupFactory $EavTablesSetupFactory
     */
    public function __construct(EavTablesSetupFactory $eavTablesSetupFactory)
    {
        $this->eavTablesSetupFactory = $eavTablesSetupFactory;
    }

    /**
     * {@inheritdoc}
     * @SuppressWarnings(PHPMD.ExcessiveMethodLength)
     * @SuppressWarnings(PHPMD.UnusedFormalParameter)
     */
    public function install(SchemaSetupInterface $setup, ModuleContextInterface $context)
    {
        $setup->startSetup();

        $tableName = HelloWorldSetup::ENTITY_TYPE_CODE;
        /**
         * Create entity Table
         */
        $table = $setup->getConnection()
            ->newTable($setup->getTable($tableName))
            ->addColumn(
                'entity_id',
                Table::TYPE_INTEGER,
                null,
                ['identity' => true, 'unsigned' => true, 'nullable' => false, 'primary' => true],
                'Entity ID'
            )->setComment('Entity Table');

        $table->addColumn(
            'entity_type_id',
            Table::TYPE_SMALLINT,
            null,
            [
                'unsigned' => true,
                'nullable' => false,
                'default' => '0',
            ],
            'Entity Type ID'
        )->addIndex(
            $setup->getIdxName($tableName, ['entity_type_id']),
            ['entity_type_id']
        )->addForeignKey(
            $setup->getFkName(
                'rh_helloworld_helloworld',
                'entity_type_id',
                'eav_entity_type',
                'entity_type_id'
            ),
            'entity_type_id',
            $setup->getTable('eav_entity_type'),
            'entity_type_id',
            \Magento\Framework\DB\Ddl\Table::ACTION_CASCADE,
            \Magento\Framework\DB\Ddl\Table::ACTION_CASCADE
        );

        $table->addColumn(
            'attribute_set_id',
            Table::TYPE_SMALLINT,
            null,
            [
                'unsigned' => true,
                'nullable' => false,
                'default' => '0',
            ],
            'Attribute Set ID'
        )->addIndex(
            $setup->getIdxName($tableName, ['attribute_set_id']),
            ['attribute_set_id']
        )->addForeignKey(
            $setup->getFkName(
                'rh_helloworld_helloworld',
                'attribute_set_id',
                'eav_attribute_set',
                'attribute_set_id'
            ),
            'attribute_set_id',
            $setup->getTable('eav_attribute_set'),
            'attribute_set_id',
            \Magento\Framework\DB\Ddl\Table::ACTION_CASCADE,
            \Magento\Framework\DB\Ddl\Table::ACTION_CASCADE
        );

        // Add more static attributes here...

        $table->addColumn(
            'created_at',
            Table::TYPE_TIMESTAMP,
            null,
            ['nullable' => false, 'default' => Table::TIMESTAMP_INIT],
            'Creation Time'
        )->addColumn(
            'updated_at',
            Table::TYPE_TIMESTAMP,
            null,
            ['nullable' => false, 'default' => Table::TIMESTAMP_INIT_UPDATE],
            'Update Time'
        );

        $setup->getConnection()->createTable($table);

        /** @var \RH\HelloWorld\Setup\EavTablesSetup $eavTablesSetup */
        $eavTablesSetup = $this->eavTablesSetupFactory->create(['setup' => $setup]);
        $eavTablesSetup->createEavTables(HelloWorldSetup::ENTITY_TYPE_CODE);

        $setup->endSetup();
    }
}

HelloWorldSetup.php :

<?php
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */

/**
 * Code standard by : RH
 */
namespace RH\HelloWorld\Setup;

use Magento\Eav\Model\Entity\Attribute\ScopedAttributeInterface;
use Magento\Eav\Setup\EavSetup;

class HelloWorldSetup extends EavSetup {
    /**
     * Entity type for Hello World EAV attributes
     */
    const ENTITY_TYPE_CODE = 'rh_helloworld_helloworld';

    /**
     * EAV Entity type for Hello World EAV attributes
     */
    const EAV_ENTITY_TYPE_CODE = 'rh_helloworld';

    /**
     * Retrieve Entity Attributes
     *
     * @return array
     * @SuppressWarnings(PHPMD.ExcessiveMethodLength)
     */
    protected function getAttributes() {
        $attributes = [];

        $attributes['main_title'] = [
            'group' => 'General',
            'type' => 'varchar',
            'label' => 'Main Title',
            'input' => 'text',
            'global' => ScopedAttributeInterface::SCOPE_STORE,
            'required' => '1',
            'user_defined' => false,
            'default' => '',
            'unique' => false,
            'position' => '10',
            'note' => '',
            'visible' => '1',
            'wysiwyg_enabled' => '0',
        ];

        // Add your more entity attributes here...

        return $attributes;
    }

    /**
     * Retrieve default entities
     *
     * @return array
     */
    public function getDefaultEntities() {
        $entities = [
            self::ENTITY_TYPE_CODE => [
                'entity_model' => 'RH\HelloWorld\Model\ResourceModel\HelloWorld',
                'attribute_model' => 'RH\HelloWorld\Model\ResourceModel\Eav\Attribute',
                'table' => self::ENTITY_TYPE_CODE,
                'increment_model' => null,
                'additional_attribute_table' => 'rh_helloworld_eav_attribute',
                'entity_attribute_collection' => 'RH\HelloWorld\Model\ResourceModel\Attribute\Collection',
                'attributes' => $this->getAttributes(),
            ],
        ];

        return $entities;
    }
}

For more, You can take reference from here. It maybe helpful for you.

Reference