Save the date the TOS was checked at checkout with Paid Memberships Pro

my_pmpro_after_checkout_tos_save.php

//add field to profile
function my_pmprorh_init()
{
  if(!function_exists("pmprorh_add_registration_field"))
    return;
  
  $secret = new PMProRH_Field("tos_checked_date", "readonly", array("profile"=>"admin", "label"=>"TOS Checked Date"));
  pmprorh_add_registration_field("checkout_boxes", $secret);
}

//save after checkout
function my_pmpro_after_checkout_tos_save($user_id)
{
  if(!empty($_REQUEST['tos']))
  {
    update_user_meta($user_id, "tos_checked_date", date(get_option("date_format")));
    update_user_meta($user_id, "tos_checked_ip", get_the_user_ip());
  }
}
add_action('pmpro_after_checkout', 'my_pmpro_after_checkout_tos_save');

//from: http://www.wpbeginner.com/wp-tutorials/how-to-display-a-users-ip-address-in-wordpress/
function get_the_user_ip() {
  if ( ! empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
  //check ip from share internet
  $ip = $_SERVER['HTTP_CLIENT_IP'];
  } elseif ( ! empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
  //to check ip is pass from proxy
  $ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
  } else {
  $ip = $_SERVER['REMOTE_ADDR'];
  }
  return apply_filters( 'wpb_get_ip', $ip );
}