shopify application charge failing to save

Question

Below is my code for a Shopify one-time-application-charge in Ruby. I followed the shopify "add billing to your app" page (https://help.shopify.com/api/tutorials/adding-billing-to-your-app) for the code, except didn't need a recurring charge. I have also found someone else who posted their one-time-charge code which looks very similar to mine (https://ecommerce.shopify.com/c/shopify-apis-and-technology/t/one-time-application-charge-example-for-shopify-rails-app-489347).

def create_application_charge

       application_charge = ShopifyAPI::ApplicationCharge.new(
            name: "MyApp",
            price: 0.09,
            return_url: "https:\/\/myapp.herokuapp.com\/activatecharge",
            test: true)
        save = application_charge.save
        if save
            redirect application_charge.confirmation_url
            return
        end
        flash[:error] = "The save worked: #{save}"
    end

The flash always responds as false. Is there a failure at authentication that would prevent this? Or something to get the store to accept an application charge? I'm at a loss as to why this does not work.

Any help would be greatly appreciated, thank you.

Answer 1

The primary issue appears to be that the minimum charge you can request is $0.50, for which I wasn't meeting with my choice of using $0.09 for my test.