Re: [Taler] Android Taler Wallet bug

[Marc Stibane]

> On 2024-01-09, at 21:28:57, Jonathan Krebs <jonathan.krebs@bruckbu.de> wrote:
> On 09.01.24 21:16, Marc Stibane via Taler wrote:
>>> On 2024-01-09, at 20:57:20, Slack Coder <slackcoder@server.ky> wrote:
>>> 
>>> When the same fulfillment URL is used for a second order, it results in an 
>>> "You've already paid for this purchase" error.  This feels unexpected 
>>> because its an entirely different order.
>> 1) May a fulfillment URI be reused?
> No: 
> https://docs.taler.net/taler-merchant-api-tutorial.html#repurchase-detection-and-fulfillment-urls
> 
> > To ensure this mechanism works as designed, merchants must make sure to not 
> > use the same fulfillment URL for different products or for physical 
> > products where customers may be expected to buy the article repeatedly. 
> > Similarly, it is crucial that merchants consistently use the same 
> > fulfillment URL for the same digital product where repurchase detection is 
> > desired.

Yeah, that’s what I was thinking. You can only use the same fulfillment URL for 
a virtual good (such as a book chapter on the Taler demo shop), where the 
customer should get access a second time instead of paying again.


> You can use the token $ORDER_ID in the fulillement url when creating the 
> order, it gets replaced by the merchant backend with the actual order id, to 
> create a unique url.



However the Wallet app/webex shouldn’t show an "error" - but rather a hint to 
the user that they should be able to get access to the product without paying 
again.

Thus this is no "Android Taler Wallet bug”, but a general wallet UI/UX issue, 
which should be tracked in Mantis (with low priority).


Marc