How can we see which posts don't have a featured image or it doesn't exist anymore?

Question

Which plugin or code I need to make it show me a list with the posts that don't have featured image or is broken(the featured image doesn't exist anymore)?

Answer 1

In form of a shortcode:

add_shortcode('nofeatures', 'wpse_51768_shortcode');
function wpse_51768_shortcode() {
    $posts = get_posts( array('numberposts' => -1) );
    foreach ( $posts as $post ) {
        $featured = get_the_post_thumbnail( $post->ID, 'thumbnail', null );
        if ( $featured ) echo 'Has Featured Image: ' . $post->post_title . '<br />';
    }
}

[update]

The following outputs the posts that don't have a Featured Image, and if it has one, check if the file is live:

add_shortcode('nofeatures', 'shortcode_wpse_51768');

function shortcode_wpse_51768() 
{
    $args = array(
        'numberposts' => -1,
        'post_type'   => 'post',
        'post_status' => 'publish'
    );
    $posts = get_posts( $args );

    foreach ( $posts as $post ) 
    {
        $featured = has_post_thumbnail( $post->ID );

        if ( !$featured ) 
            echo "<p>Doesn't have Featured Image: <b>" . $post->post_title . "</b></p>";
        else
        {
            $thumb = wp_get_attachment_image_src( get_post_thumbnail_id( $post->ID ), 'full' );
            $is_live = check_if_featured_image_is_live( $thumb[0] );
            if ( !$is_live )
                echo '<p>Featured image 404: <b>' . $post->post_title . '</b></p>';
        }
    }
}

// http://stackoverflow.com/a/7953100/1287812
function check_if_featured_image_is_live($url)
{
    $options['http'] = array(
        'method' => "HEAD",
        'ignore_errors' => 1,
        'max_redirects' => 0
    );
    $body = file_get_contents($url, NULL, stream_context_create($options));
    sscanf($http_response_header[0], 'HTTP/%*d.%*d %d', $code);
    return $code === 200;
}