Add a metabox to admin WooCommerce Product if it has specific product tag

I am really struggling with WooCommerce PHP. This time I am simply trying to see if a product post has a tag before continuing to add a custom metabox. The code is written into functions.php of the child theme.

global $wp_query;
$id = $wp_query->post->ID;

if ( ! has_tag( "hasparts", $id )) {
    die; // used return also
    } else {
        // add metabox
}

I get the following error

Warning: Attempt to read property "ID" on null in C:\xampp\htdocs\wiz_invent\wp-content\themes\storefront-child\functions.php on line 14

I do not seem to be able to get my head around how to find basic post properties (ID, SKU) or how and where to use $post variable.

WooCommerce Tag is a custom taxonomy, so it will work with WordPress has_term() and product_tag taxonomy for WooCommerce tag.

Below is a complete example based on your requirement:

// Add a metabox to WooCommerce Product conditionally
add_action( 'add_meta_boxes', 'admin_product_custom_metabox' );
function admin_product_custom_metabox() {

    if( has_term( array('hasparts'), 'product_tag') ) {

        add_meta_box(
            'custom',
            __('Custom Meta Box'),
            'custom_metabox_content_callback',
            'product',
            'normal',
            'high'
        );
    }
}

// Metabox content callback function
function custom_metabox_content_callback() {
    echo 'Here goes the metabox content…';
}

Code goes on functions.php file of your child theme (or in a plugin). Tested and works.