PHP Warning: Undefined array key “post_type” in class-backend.php

Environment:

• WordPress 7.1
• PHP 8.3.33
• WooCommerce 11.0.1
• Server: Apache

Description:

Getting the following warning in the logs:

PHP Warning: Undefined array key "post_type" in [site]/wp-content/plugins/search-exclude/lib/controllers/class-backend.php on line 173

Cause:

Line 173 reads $_REQUEST['post_type'] directly without checking whether the key exists first:

php

public function save_post_ids_to_search_exclude( $post_ids, $exclude ) {
    $post_type = $_REQUEST['post_type'];

On PHP 8.0+, accessing an undefined array key raises a warning instead of silently returning NULL (as it did on PHP 7.x). Since save_post_ids_to_search_exclude() is presumably being called (directly or via a hook) in a request that doesn’t include a post_type parameter, this fires every time.

Suggested fix:

Use isset() with the null coalescing operator so it degrades gracefully when post_type isn’t present:

php

$post_type = isset( $_REQUEST['post_type'] ) ? sanitize_key( $_REQUEST['post_type'] ) : '';

(Adding sanitize_key() here too, since this is unsanitized $_REQUEST input being used as an array key shortly after.)

Impact:

Cosmetic/log-noise only in my case so far — doesn’t appear to break functionality — but it’s worth fixing since PHP is trending toward stricter handling of undefined array access in future versions, and it clutters error logs on sites with logging/monitoring enabled.