I am implementing a Shopify Store into a WordPress theme and one thing I need for that is a way to query Shopify products with the product handle instead of ID as shown on their docs:

<http://shopify.github.io/js-buy-sdk/api/classes/ShopClient.html#method-fetchProduct>

The reason for this is what I want to have the single product view with a SEO friendly URL, built precisely from the product handle. 

On Shopify's site someone mentions a non-documented way to achieve this, I couldn't however get it to work:
<https://ecommerce.shopify.com/c/shopify-apis-and-technology/t/how-do-i-query-for-a-product-using-its-handle-322118#comment-346792>

Have anyone had luck with this?