PHP get all product tags in WooCommerce

Insert this code into your WordPress theme’s functions.php:

function tqt_vtdevs_get_product_tags(){
    $args = array(
        'taxonomy'     => 'product_tag',
        'orderby'      => 'name',
        'order'        => 'ASC',
        'hide_empty'   => false,
    );
    $all_product_tag = array();
    // $cus_product_tag = array();
    $the_query = new WP_Term_Query($args);
    $all_terms = $the_query->get_terms();
    if ( empty( $all_terms ) || is_wp_error( $all_terms ) ) {
        echo '$the_query->get_terms() is error.';
        exit;
    }
    foreach($the_query->get_terms() as $term) {
        $all_product_tag[] = $term;
        // if ($term->slug == 'special-edition-product') $cus_product_tag[] = $term;
    }
    print_r($all_product_tag);
    // print_r($cus_product_tag);
    exit;
}
if (!empty($_GET['gtags'])) {
    tqt_vtdevs_get_product_tags();
    exit;
}

Output:

Array
(
    [0] => WP_Term Object
        (
            [term_id] => 3451
            [name] => Special Edition
            [slug] => special-edition
            [term_group] => 0
            [term_taxonomy_id] => 3451
            [taxonomy] => product_tag
            [description] => 
            [parent] => 0
            [count] => 5
            [filter] => raw
        )
…
)