I am testing the python paypalrestsdk. I am successfully creating an Invoice, however it is defined as SALE for payment type. I would like to create is as an "authorization" to capture it later. How can I do that?
To my knowledge, the Invoicing API does not support Auth and Capture directly.
If you want that functionality you would need to build your own invoicing system. You could setup a simple HTML invoice, for example, and when your buyer clicks to pay it would send them through a regular Pay Checkout flow with PayPal. This way you could go ahead and use Auth and Capture.
Of course, this means you'll also need to build your own invoice manager, because it won't be available as an actual invoice inside your PayPal account like it is when you use the Invoicing API. But, you'd have the flexibility to do what you're wanting.
Angell EYE - www.angelleye.com PayPal Partner and Certified Developer - Kudos are Greatly Appreciated!