VIES Validation App Manual for AI Coding Agent

Introduction

This manual provides a step-by-step guide on how to create a working validation app with a connection to the VIES API. The app will integrate with the VIES API to validate EU VAT numbers in real-time during the WooCommerce checkout process.

Prerequisites

• WooCommerce plugin installed and configured on a WordPress website
• VIES API credentials:
  • Identifier: gix6YlXAxKYg
  • Key: QNoJ0VsGPtef
• Basic knowledge of PHP, WordPress, and WooCommerce development

Step 1: Integrate with VIES API

Create a new PHP file in the WordPress plugin directory (e.g., vies-api.php) and add the following code to connect to the VIES API:

function vies_api_connect() {
  $identifier = 'gix6YlXAxKYg';
  $key = 'QNoJ0VsGPtef';
  $api_url = 'https://api.viesapi.eu/vat/';
  $headers = array(
    'Authorization' => 'Basic ' . base64_encode($identifier . ':' . $key)
  );
  return $api_url;
}

Use the vies_api_connect() function to retrieve the API URL and store it in a variable.

Step 2: Add VAT Number Input Field to WooCommerce Checkout Page

Create a new PHP file in the WordPress plugin directory (e.g., woocommerce-vat-field.php) and add the following code to add a VAT number input field to the WooCommerce checkout page:

function add_vat_field_to_checkout() {
  woocommerce_form_field(
    'vat_number',
    array(
      'label' => __('VAT Number', 'woocommerce'),
      'placeholder' => __('Enter your VAT number', 'woocommerce'),
      'required' => true,
      'class' => array('form-row-wide'),
      'clear' => true
    )
  );
}
add_action('woocommerce_checkout_before_order_review', 'add_vat_field_to_checkout');

This code will add a new input field to the WooCommerce checkout page with the label “VAT Number”.

Step 3: Validate EU VAT Numbers in Real-Time

Create a new PHP file in the WordPress plugin directory (e.g., vies-validation.php) and add the following code to validate EU VAT numbers in real-time:

function validate_vat_number($vat_number) {
  $api_url = vies_api_connect();
  $response = wp_remote_get($api_url . $vat_number, array(
    'headers' => array(
      'Authorization' => 'Basic ' . base64_encode('gix6YlXAxKYg:QNoJ0VsGPtef')
    )
  ));
  $body = wp_remote_retrieve_body($response);
  $data = json_decode($body, true);
  if ($data['valid']) {
    return true;
  } else {
    return false;
  }
}

Use the validate_vat_number() function to validate the VAT number entered by the user.

Step 4: Store Validated VAT Information in Order Metadata

Create a new PHP file in the WordPress plugin directory (e.g., woocommerce-vat-metadata.php) and add the following code to store validated VAT information in order metadata:

function store_vat_metadata($order_id) {
  $vat_number = $_POST['vat_number'];
  $is_valid = validate_vat_number($vat_number);
  if ($is_valid) {
    update_post_meta($order_id, '_vat_number', $vat_number);
    update_post_meta($order_id, '_vat_valid', 'yes');
  } else {
    update_post_meta($order_id, '_vat_valid', 'no');
  }
}
add_action('woocommerce_new_order', 'store_vat_metadata');

This code will store the validated VAT number and its validity status in the order metadata.

Conclusion

By following these steps, you should now have a working validation app that integrates with the VIES API to validate EU VAT numbers in real-time during the WooCommerce checkout process. The validated VAT information will be stored in the order metadata for future reference.

Example Use Case

1. A customer enters their VAT number during the WooCommerce checkout process.
2. The validate_vat_number() function is called to validate the VAT number in real-time.
3. If the VAT number is valid, the store_vat_metadata() function is called to store the validated VAT information in the order metadata.
4. The customer completes the checkout process, and the order is created with the validated VAT information stored in its metadata.

Note: This is a basic example, and you may need to modify the code to fit your specific requirements. Additionally, you should ensure that you are complying with all relevant laws and regulations regarding VAT validation and storage.