Export WooCommerce Subscriptions to CSV. Provides a `Export Subscriptions` button in Woo admin menu

export_woo_subscriptions_to_csv.php

<?php

/**
 * Plugin Name:       Export WooCommerce subscriptions
 * Plugin URI:        https://www.blue37.com/
 * Description:       Export WooCommerce subscriptions to a CSV file.
 * Version:           0.0.1
 * Requires at least: 6.0
 * Requires PHP:      8.0
 * Author:            Blue 37
 * Author URI:        https://blue37.com/
 * License:           GPL v2 or later
 * License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 * Text Domain:       ews
 * Domain Path:       /ews
 *
 * @package EWS\export_woo_subscriptions
 */

// Exit if accessed directly.
if (!defined('ABSPATH')) {
  die('Access denied.');
}

/**
 * Export WooCommerce subscriptions to a CSV file.
 *
 * This function checks if the current user has administrative permissions and
 * if the 'export_subscriptions' query parameter is set. If both conditions are met,
 * it queries all subscriptions using WooCommerce Subscriptions, writes them to a CSV file,
 * and sends the file to the browser for download.
 *
 * @hooked admin_init - 10
 */
function ews_export_subscriptions_to_csv() {
    // Check if the user has administrative permissions and if the export query parameter is set
    if (current_user_can('manage_options') && isset($_GET['export_subscriptions'])) {
        // Set the CSV content type and file name in the headers
        header('Content-Type: text/csv');
        header('Content-Disposition: attachment; filename="subscriptions.csv"');

        // Open a stream to send the CSV output to the browser
        $output = fopen('php://output', 'w');

        // Write the header row of the CSV file
        fputcsv($output, array('Subscription ID', 'Status', 'Customer Email', 'Customer First Name', 'Customer Last Name', 'Start Date', 'End Date', 'Next Payment Date', 'Total'));

        // Query all subscriptions from WooCommerce Subscriptions
        $subscriptions = wcs_get_subscriptions(array('subscriptions_per_page' => -1));

        // Loop through the subscriptions and write each one to the CSV file
        foreach ($subscriptions as $subscription) {
            $data = array(
                'Subscription ID'       => $subscription->get_id(),
                'Status'                => $subscription->get_status(),
                'Customer Email'        => $subscription->get_billing_email(),
                'Customer First Name'   => $subscription->get_billing_first_name(),
                'Customer Last Name'    => $subscription->get_billing_last_name(),
                'Start Date'            => $subscription->get_date('start'),
                'End Date'              => $subscription->get_date('end'),
                'Next Payment Date'     => $subscription->get_date('next_payment'),
                'Total'                 => $subscription->get_total()
            );
            fputcsv($output, $data);
        }

        // Close the output stream
        fclose($output);
        
        // Terminate the script to ensure no additional output is sent
        exit;
    }
}
add_action('admin_init', 'ews_export_subscriptions_to_csv');

/**
 * Add a custom link to the WooCommerce menu to export subscriptions.
 */
function ews_add_export_subscriptions_link() {
    global $submenu;

    $submenu['woocommerce'][] = array(
        'Export Subscriptions',
        'manage_options',
        admin_url('?export_subscriptions=1')
    );
}
add_action('admin_menu', 'ews_add_export_subscriptions_link');