API Token in your WP admin). Identifies * YOU as the seller - never expose this to customers or in JS. */ const API_TOKEN = 'YOUR_LICFY_API_TOKEN'; /** * The exact product slug you registered under Licfy -> Products. */ const PRODUCT_SLUG = 'my-awesome-plugin'; /** wp_options key used to store the customer's entered license key. */ const OPTION_LICENSE_KEY = 'my_plugin_license_key'; /** transient key used to cache the last verification result. */ const TRANSIENT_STATUS = 'my_plugin_license_status'; /** * Wire up the settings page and the activate/deactivate handlers. */ public static function init() { add_action( 'admin_menu', array( __CLASS__, 'register_settings_page' ) ); add_action( 'admin_post_my_plugin_activate_license', array( __CLASS__, 'handle_activate' ) ); add_action( 'admin_post_my_plugin_deactivate_license', array( __CLASS__, 'handle_deactivate' ) ); add_action( 'admin_notices', array( __CLASS__, 'maybe_show_inactive_notice' ) ); } /** * Settings > My Plugin License page with the key input + activate/deactivate form. */ public static function register_settings_page() { add_options_page( __( 'My Plugin License', 'my-plugin' ), __( 'My Plugin License', 'my-plugin' ), 'manage_options', 'my-plugin-license', array( __CLASS__, 'render_settings_page' ) ); } public static function render_settings_page() { $license_key = get_option( self::OPTION_LICENSE_KEY, '' ); $is_active = self::is_active(); ?>

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'error'] shape on failure. */ public static function verify( $license_key ) { $response = wp_remote_post( self::API_BASE . '/verify', array( 'timeout' => 15, 'headers' => array( 'Authorization' => 'Bearer ' . self::API_TOKEN, 'Content-Type' => 'application/json', ), 'body' => wp_json_encode( array( 'email' => get_option( 'admin_email' ), 'license_key' => $license_key, 'product_slug' => self::PRODUCT_SLUG, 'website_name' => get_bloginfo( 'name' ), 'website_url' => home_url(), ) ), ) ); if ( is_wp_error( $response ) ) { return array( 'status' => 'error', 'message' => $response->get_error_message() ); } $data = json_decode( wp_remote_retrieve_body( $response ), true ); return is_array( $data ) ? $data : array( 'status' => 'error', 'message' => 'Unexpected response' ); } /** * Whether the stored license key is currently valid. Result is cached for a * day so premium features aren't blocked by an API call on every page load. * * @return bool */ public static function is_active() { $cached = get_transient( self::TRANSIENT_STATUS ); if ( false !== $cached ) { return 'valid' === $cached; } $license_key = get_option( self::OPTION_LICENSE_KEY ); if ( ! $license_key ) { return false; } $result = self::verify( $license_key ); $status = ( ! empty( $result['license_status'] ) && 'valid' === $result['license_status'] ) ? 'valid' : 'invalid'; set_transient( self::TRANSIENT_STATUS, $status, DAY_IN_SECONDS ); return 'valid' === $status; } /** * Admin notice nudging the site owner to activate their license. */ public static function maybe_show_inactive_notice() { if ( self::is_active() || ! current_user_can( 'manage_options' ) ) { return; } ?>

' . esc_html__( 'Activate your license', 'my-plugin' ) . '' ); ?>