Fallback image

Hi there,

Yes, you can modify your code like this:

add_filter('generateblocks_dynamic_tag_output', function ($output, $options) {
    $tag_name = $options['tag_name'] ?? '';

    if ('featured_image' === $tag_name) {

        if (empty($output)) {
            if (is_singular('event')) {
                return 'url for event fallback featured image';
            }

            return 'https://my-website.org.uk/wp-content/uploads/2025/10/my-image.jpg';
        }
    }

    return $output;
}, 10, 2);

Let me know if this works!

You are welcome   🙂

Thanks for sharing and explaining 🙂

Try this PHP code instead, it adds a fallback image directly to the event post type instead of adding it based on the dynamic tag:

function add_fallback_featured_image( $value, $post_id, $meta_key, $single ) {
    // Only modify when retrieving the featured image
    if ( $meta_key === '_thumbnail_id' && empty( $value ) && !is_admin() ) {
        // Check if this is an 'event' post type
        if ( get_post_type( $post_id ) === 'event' ) {
            // Return your fallback image ID
            return 11; // <-- Use your fallback image ID (integer, not string)
        }
    }

    // Otherwise, return the original value
    return $value;
}
add_filter( 'get_post_metadata', 'add_fallback_featured_image', 50, 4 );

I updated the code https://generate.support/topic/fallback-image/#post-183267, and this time we use the image ID, so replace 11 with the actual image ID that you can find in the URL when viewing the image via the media library.

Hi Lindsay,

I’ve made a few adjustments to the snippet, can you give this version a try:

function add_fallback_featured_image( $value, $post_id, $meta_key, $single ) {
    // Only modify when retrieving the featured image
    if ( $meta_key === '_thumbnail_id' && !is_admin() ) {
        // Check if this is an 'event' post type
        if ( get_post_type( $post_id ) === 'event' ) {
            // IMPORTANT: Check if a featured image actually exists
            // We need to do a direct database check to avoid infinite loop
            global $wpdb;
            $actual_thumbnail = $wpdb->get_var( $wpdb->prepare(
                "SELECT meta_value FROM $wpdb->postmeta WHERE post_id = %d AND meta_key = '_thumbnail_id'",
                $post_id
            ));
            
            // Only return fallback if no thumbnail exists in database
            if ( empty( $actual_thumbnail ) ) {
                return 11; // Your fallback image ID
            }
        }
    }
    
    // Return null to continue with normal metadata retrieval
    return $value;
}
add_filter( 'get_post_metadata', 'add_fallback_featured_image', 50, 4 );

The original code was checking empty($value), but $value is null by default when the filter runs, regardless of whether a featured image exists or not. This caused it to always return the fallback image.

Glad to hear that! 🙂