How to check if custom product attribute exists

Question

I want to check if my custom product attributes exist before I attempt to utilize it in any way. Whats the best way to check it in Magento 2.

Note that I don't want to check if specific product has the attribute. I want to check if that attribute exists in Magento.

I've found partial answer on stackexchange https://magento.stackexchange.com/a/107993/14809

but that answer is very limited. Especially the code example is very scarce:

try {
   $attribute = $this->attributeRepository->get($entityType, $attributeCode);
} catch (\Magento\Framework\Exception\NoSuchEntityException $e) {
    //  attribute is not exists
}

1. It's not clear what to enter in $entityType.
2. What will get return if the attribute does not exist?
3. I don't know where to find example implementation of the methods (e.g. get(...)) defined in the interface \Magento\Eav\Api\AttributeRepositoryInterface.php

Answer 1

1. $entityType in your case is the 'catalog_product' as its a product attribute
2. It will throw an exception
3. vendor/magento/module-eav/Model/AttributeRepository.php and check the public function get($entityTypeCode, $attributeCode)

Answer 2

You can inject Magento\Eav\Model\Config object and use the getAttribute('catalog_product', $attributecode) function to check if your custom eav attribute with code $attributecode already exist or not.

Here is the code sample:

$attribute = $this->eavConfig->getAttribute($entityTypeCode, $attributeCode);
if (!$attribute || !$attribute->getAttributeId()) {
    throw new NoSuchEntityException(
        __('Attribute with attributeCode "%1" does not exist.', $attributeCode)
    );
}
return $attribute;

Answer 3

Check "eav_entity_type" table. It will show you all the attribute type code you can use while fetching the information.