WooCommerce programmatically create variations from all attributes

gistfile1.txt

<?php
  
    /* 
        WooCommerce has a handy feature in the admin UI to "Create variations from all attributes". 
        To do this programmatically (as of WooCommerce v3.7.0) use a modified version of link_all_variations() found in woocommerce/includes/class-wc-ajax.php
    */
    function myplugin_create_variations($product_id){

        wc_maybe_define_constant( 'WC_MAX_LINKED_VARIATIONS', 50 );
        wc_set_time_limit( 0 );
        if ( ! $product_id ) {
        	wp_die();
        }
        $product    = wc_get_product( $product_id );
        $data_store = $product->get_data_store();
        if ( ! is_callable( array( $data_store, 'create_all_product_variations' ) ) ) {
        	wp_die();
        }
        echo esc_html( $data_store->create_all_product_variations( $product, WC_MAX_LINKED_VARIATIONS ) );
        $data_store->sort_all_product_variations( $product->get_id() );  

    }//myplugin_create_variations()
    
?>