Create a Sale with existing Stripe customer without credit card (yet)

[Alagaesia93]

Hey, in my app after a User is registered a free subscription is created on Stripe. Then the user can subscribe multiple plans (Payola::Subscripitons) or buy one-time licences (Payola::Sale). He can do them at same time, like a shopping cart, and if I haven't created earlier a Stripe User (getting stripe_customer_id) I have multiple customers on Stripe.

If I try to buy one Product I have 400 bad request. I've been digging into code.

Started POST "/it/payola/buy/optional/p1" for 127.0.0.1 at 2017-11-21 10:28:24 +0100 Processing by Payola::TransactionsController#create as */*

https://github.com/payolapayments/payola/blob/master/app/controllers/payola/transactions_controller.rb#L18

def create
      create_object(Sale, CreateSale, ProcessSale, :product, @product)
end

https://github.com/payolapayments/payola/blob/2cbecc0e853504c233e633311e375497b6f2bbf3/app/controllers/concerns/payola/async_behavior.rb#L18

On line 34 object = object_creator_class.call(create_params)

https://github.com/payolapayments/payola/blob/c5a5c705621d885fe39aba196c1df524898fe991/app/services/payola/create_sale.rb#L3

I have a stripe_customer_id, so in line 11 customer.default_source is null. It is correct, because my User is registered, but he has not a card yet. But there is a credit card and I have a valid params[:stripeToken]

400 Bad Request StripeToken can't be blank

Possible fix for line 11: token = customer.default_source || params[:stripeToken]

[CLAassistant]

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[Alagaesia93]

There is a 400 bad request anyway later in render_payola_subscription. Error is "cannot charge a customer without a valid payments source".

Sorry, this pull request does not fix everything