After debugging and ensuring that the data persistence logic is correct, what may be cause and solution to this?

An Adobe Commerce Developer is tasked with creating a custom form which submits its data to a frontend controller They have decided to create an action and have implemented the MagentoFrameworkAppActionHttpPostActioninterface class, but are not seeing the data being persisted in the database, and an error message is being shown on the frontend after submission.

After debugging and ensuring that the data persistence logic is correct, what may be cause and solution to this?
A . Magento does not allow POST requests to a frontend controller, therefore, the submission functionality will need to be rewritten as an API endpoint.
B. The developer forgot to implement a validatePostDataQ method in their action. They should implement this method: all non-validated POST data gets stripped out of the request and an error is thrown.
C. Form key validation runs on all non-AJAX POST requests, the developer needs to add the for_key to their requests.

View Answer

Answer: C

Explanation:

According to the Magento Stack Exchange answer, form key validation is a security feature that prevents CSRF attacks by checking if the form key in the request matches the one generated by Magento. If the developer does not include the form_key in their custom form, the validation will fail and an error will be shown. Therefore, the developer needs to add the form_key to their requests by using <?= $block->getBlockHtml (‘formkey’) ?> in their template file.

Reference: https://magento.stackexchange.com/questions/95171/magento-2-form-validation