Gsyfuy

Does Magento 2 have a high level abstraction that allows end-user-programmers to update configuration values in the core_config_data table? Or is using straight SQL the only way to do this in Magento 2?

i.e. in Magento 1, you could do something like this

$config_model = new Mage_Core_Model_Config();

$config_model->saveConfig('my/config/path', $unique_id, 'default', 0);

and save configuration values into core_config_data. Is there an equivalent in Magento 2?

There is the same saveConfig method: https://github.com/magento/magento2/blob/2.0.0/app/code/Magento/Config/Model/ResourceModel/Config.php#L26-L61

A usage example from the core: https://github.com/magento/magento2/blob/2.0.0/app/code/Magento/Payment/Observer/UpdateOrderStatusForPaymentMethodsObserver.php#L59-L64

I wouldn't use a model or a resource model, but MagentoFrameworkAppConfigStorageWriterInterface or MagentoFrameworkAppConfigConfigResourceConfigInterface (the first delegating to the second).

Pretty straight-forward, too:

use MagentoFrameworkAppConfigStorageWriterInterface;



class SomeClass {



    public function __construct(WriterInterface $configWriter)

    {

        $configWriter->save('some/config/path', 'some value');

    }

}

You can also use MagentoConfigModelConfig::save. Below a simple sample:

$configData = [

    'section' => 'MY_SECTION',

    'website' => null,

    'store'   => null,

    'groups'  => [

        'MY_GROUP' => [

            'fields' => [

                'MY_FIELD' => [

                    'value' => $myValue,

                ],

            ],

        ],

    ],

];



// $this->configFactory --> MagentoConfigModelConfigFactory

/** @var MagentoConfigModelConfig $configModel */

$configModel = $this->configFactory->create(['data' => $configData]);

$configModel->save();

This syntax is not "simple", but it's more safe for some case.
Du to the save logic, the action might be slower than direct access to the db.

In my case, $value need to be encrypted. In system.xml, I set the backend model for the field, and the save logic encrypt the data.

Edit: MagentoConfigModelConfig::setDataByPath more simple to use

For a high level abstraction I'd inject MagentoFrameworkAppConfigStorageWriterInterface into the constructor of a data setup script:

use MagentoFrameworkAppConfigStorageWriterInterface; 



public function __construct(WriterInterface $configWriter) {...}

Then use the save() method, for example:

$website = $this->websiteRepository->get('main_website'); // inject MagentoStoreModelWebsiteRepository;



$this->configWriter->save('general/country/default', 'US', ScopeInterface::SCOPE_WEBSITES, $website->getId()); // inject MagentoStoreModelScopeInterface;

Notes:
Use the plural form of scopes: websites / stores in MagentoStoreModelScopeInterface

Here a complete sample to handle Magento 2 configuration programatically.

In my case, i add to clear cache too, else changes does not appear in Store > Config.

/**

 * @var MagentoConfigModelResourceModelConfig

 */

protected $resourceConfig;



/**

 * @var MagentoFrameworkAppCacheTypeListInterface

 */

protected $cacheTypeList;



public function __construct(

    MagentoConfigModelResourceModelConfig $resourceConfig,

    MagentoFrameworkAppCacheTypeListInterface $cacheTypeList

) {

    $this->resourceConfig = $resourceConfig;

    $this->cacheTypeList = $cacheTypeList;

}



public function process()

{

    $this->resourceConfig->saveConfig(

        'my/config/path',

        $unique_id,

        MagentoFrameworkAppScopeInterface::SCOPE_DEFAULT,

        0

    );

     $this->cacheTypeList->cleanType(MagentoFrameworkAppCacheTypeConfig::TYPE_IDENTIFIER);

}