How is a backend email template dropdown implemented?

dmitry_fedyuk · June 25, 2017, 11:05am

etc/adminhtml/system.xml

magento/magento2/blob/2.2.0-RC1.1/app/code/Magento/Sales/etc/adminhtml/system.xml#L146-L150


<field id="template" translate="label comment" type="select" sortOrder="2" showInDefault="1" showInWebsite="1" showInStore="1" canRestore="1">
    <label>New Order Confirmation Template</label>
    <comment>Email template chosen based on theme fallback when "Default" option is selected.</comment>
    <source_model>Magento\Config\Model\Config\Source\Email\Template</source_model>
</field>

Magento\Config\Model\Config\Source\Email\Template::toOptionArray()

github.com

magento/magento2/blob/2.2.0-RC1.1/app/code/Magento/Config/Model/Config/Source/Email/Template.php#L43-L62


/**
 * Generate list of email templates
 *
 * @return array
 */
public function toOptionArray()
{
    /** @var $collection \Magento\Email\Model\ResourceModel\Template\Collection */
    if (!($collection = $this->_coreRegistry->registry('config_system_email_template'))) {
        $collection = $this->_templatesFactory->create();
        $collection->load();
        $this->_coreRegistry->register('config_system_email_template', $collection);
    }
    $options = $collection->toOptionArray();
    $templateId = str_replace('/', '_', $this->getPath());
    $templateLabel = $this->_emailConfig->getTemplateLabel($templateId);
    $templateLabel = __('%1 (Default)', $templateLabel);
    array_unshift($options, ['value' => $templateId, 'label' => $templateLabel]);
    return $options;
}

Magento\Email\Model\ResourceModel\Template\Collection

It is an ordinary Magento collection, which works with the email_template table.

github.com

magento/magento2/blob/2.2.0-RC1.1/app/code/Magento/Email/Model/ResourceModel/Template/Collection.php#L22-L41


/**
 * Define resource table
 *
 * @return void
 */
public function _construct()
{
    $this->_init(\Magento\Email\Model\Template::class, \Magento\Email\Model\ResourceModel\Template::class);
    $this->_templateTable = $this->getMainTable();
}


/**
 * Convert collection items to select options array
 *
 * @return array
 */
public function toOptionArray()
{
    return $this->_toOptionArray('template_id', 'template_code');
}

The `email_template` table

It is created on the Magento_Email module installation:

github.com

magento/magento2/blob/2.2.0-RC1.1/app/code/Magento/Email/Setup/InstallSchema.php#L26-L119


/**
 * Create table 'email_template'
 */
$table = $installer->getConnection()->newTable(
    $installer->getTable('email_template')
)->addColumn(
    'template_id',
    \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
    null,
    ['identity' => true, 'unsigned' => true, 'nullable' => false, 'primary' => true],
    'Template ID'
)->addColumn(
    'template_code',
    \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
    150,
    ['nullable' => false],
    'Template Name'
)->addColumn(
    'template_text',
    \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
    '64k',
    ['nullable' => false],
    'Template Content'
)->addColumn(
    'template_styles',
    \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
    '64k',
    [],
    'Templste Styles'
)->addColumn(
    'template_type',
    \Magento\Framework\DB\Ddl\Table::TYPE_INTEGER,
    null,
    ['unsigned' => true],
    'Template Type'
)->addColumn(
    'template_subject',
    \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
    200,
    ['nullable' => false],
    'Template Subject'
)->addColumn(
    'template_sender_name',
    \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
    200,
    [],
    'Template Sender Name'
)->addColumn(
    'template_sender_email',
    \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
    200,
    [],
    'Template Sender Email'
)->addColumn(
    'added_at',
    \Magento\Framework\DB\Ddl\Table::TYPE_TIMESTAMP,
    null,
    ['nullable' => false, 'default' => \Magento\Framework\DB\Ddl\Table::TIMESTAMP_INIT],
    'Date of Template Creation'
)->addColumn(
    'modified_at',
    \Magento\Framework\DB\Ddl\Table::TYPE_TIMESTAMP,
    null,
    ['nullable' => false, 'default' => \Magento\Framework\DB\Ddl\Table::TIMESTAMP_INIT_UPDATE],
    'Date of Template Modification'
)->addColumn(
    'orig_template_code',
    \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
    200,
    [],
    'Original Template Code'
)->addColumn(
    'orig_template_variables',
    \Magento\Framework\DB\Ddl\Table::TYPE_TEXT,
    '64k',
    [],
    'Original Template Variables'
)->addIndex(
    $installer->getIdxName(
        'email_template',
        ['template_code'],
        \Magento\Framework\DB\Adapter\AdapterInterface::INDEX_TYPE_UNIQUE
    ),
    ['template_code'],
    ['type' => \Magento\Framework\DB\Adapter\AdapterInterface::INDEX_TYPE_UNIQUE]
)->addIndex(
    $installer->getIdxName('email_template', ['added_at']),
    ['added_at']
)->addIndex(
    $installer->getIdxName('email_template', ['modified_at']),
    ['modified_at']
)->setComment(
    'Email Templates'
);

dmitry_fedyuk · June 25, 2017, 11:59am

How is a backend email template dropdown implemented?

etc/adminhtml/system.xml

Magento\Config\Model\Config\Source\Email\Template::toOptionArray()

Magento\Email\Model\ResourceModel\Template\Collection

The email_template table

The `email_template` table