Only on 404 page, get notice: trying to get property of non-object on nonce

Question

I am using a WordPress plugin. Everything work fine. Exect when open a 404 page, I got this notice:

Notice: Trying to get property of non-object in D:\MYWEB\InstantWP_4.3.1\iwpserver\htdocs\wordpress\wp-content\plugins\sama-author-review\user-rate.php on line 49

Line 49 looks like this:

'nonce' => wp_create_nonce('ajax-user-rate-nonce-'. $post->ID)

Here the code:

/**
 * enqueue scripts used in frontend
 *
 */
function sama_enqueue_scripts() {
    global $post, $sama_author_review;

    $ajax_vars = array(
        'url' => admin_url( 'admin-ajax.php' ),
        'nonce' => wp_create_nonce('ajax-user-rate-nonce-'. $post->ID)
    );
    // see author-review.php
    wp_localize_script( 'review', 'ajax_user_rate', $ajax_vars );
}

Is there a quick fix to resolve these error?

Answer 1

The $post global is not set on 404 pages, which leads to the error you are getting.

You can either check if

• $post is set or

• bail if the current page is a 404 page or

• do all of the above

EXAMPLE

/**
 * enqueue scripts used in frontend
 *
 */
function sama_enqueue_scripts() {
     global $post, $sama_author_review;

    if ( !isset( $post ) )
        return;

     $ajax_vars = array(
         'url' => admin_url( 'admin-ajax.php' ),
         'nonce' => wp_create_nonce('ajax-user-rate-nonce-'. $post->ID)
     );
     // see author-review.php
     wp_localize_script( 'review', 'ajax_user_rate', $ajax_vars );
}

or

/**
 * enqueue scripts used in frontend
 *
 */
function sama_enqueue_scripts() {
     global $post, $sama_author_review;

    if ( is_404() )
        return;

     $ajax_vars = array(
         'url' => admin_url( 'admin-ajax.php' ),
         'nonce' => wp_create_nonce('ajax-user-rate-nonce-'. $post->ID)
     );
     // see author-review.php
     wp_localize_script( 'review', 'ajax_user_rate', $ajax_vars );
}