Re: [Taler] Cashdesk with GNU Taler?

[Florian Jung]

A-ha!

I don't know what changed (except I withdrew 5 more coins, totalling to 15), but now I get "got error response from exchange"; and the exchange logs this:

2022-12-05T00:54:59.198329+0000 taler-exchange-httpd-38(DXP21S0H55400M503R8D3E4QXG) INFO Handling new request
2022-12-05T00:54:59.198548+0000 taler-exchange-httpd-38(5A3SYKNA84T2N3YKYTJBSR53VM) INFO Handling request (POST) for URL '/purses/FJHTHEZ1AQGDEVSBKAX2Y08TQCQJ50TVFN93FC36Q1SAQAPBK7T0/create'
2022-12-05T00:54:59.198605+0000 taler-exchange-httpd-38(5A3SYKNA84T2N3YKYTJBSR53VM) INFO Handling request (POST) for URL '/purses/FJHTHEZ1AQGDEVSBKAX2Y08TQCQJ50TVFN93FC36Q1SAQAPBK7T0/create'
2022-12-05T00:54:59.198649+0000 taler-exchange-httpd-38(5A3SYKNA84T2N3YKYTJBSR53VM) INFO Handling request (POST) for URL '/purses/FJHTHEZ1AQGDEVSBKAX2Y08TQCQJ50TVFN93FC36Q1SAQAPBK7T0/create'
2022-12-05T00:54:59.199065+0000 taler-exchange-httpd-38(5A3SYKNA84T2N3YKYTJBSR53VM) WARNING Cannot create purse: global fees not configured!
2022-12-05T00:54:59.199344+0000 taler-exchange-httpd-38(5A3SYKNA84T2N3YKYTJBSR53VM) INFO Request for `/purses/FJHTHEZ1AQGDEVSBKAX2Y08TQCQJ50TVFN93FC36Q1SAQAPBK7T0/create' completed (0)

"global fees not configured" sounds like a valid reason, but which config options are needed to fix this?

Also, can you help me understand how transferring money from wallet to wallet works on a technical level? My naive expectation is that it works the same as withdrawing via SEPA from a bank account, just that Taler coins are redeemed at the exchange in order to create a reserve, rather than using a SEPA transfer to create one. Is that about right?

How is this different from paying a merchant? I'm a bit puzzled since wallet-to-merchant existed for a long time, but wallet-to-wallet was announced as something new. It would feel natural to me to break a merchant down to "wallet-to-wallet, and then wallet-to-sepa at the end of the business day", but apparently it's handled differently.

Thanks for your patient help! :)

Florian

On 12/5/22 00:49, Christian Grothoff wrote:

> On
>       12/4/22 22:34, Florian Jung via Taler wrote:
>       
> > Hi everyone!
> >         
> >         
> >         I finally got my taler setup running so i can connect my android
> >         wallet to it, generate a withdrawal wire transfer subject, and
> >         use libeufin-cli to fake an incoming transaction on the
> >         exchange's bank account, so i actually can retrieve my talers in
> >         the wallet.
> >         
> >         
> >         
> >         Now the next question is how do I give a customer some talers in
> >         exchange for real cash money. I see two options:
> >         
> >         
> >         - The cash-desk-guy has a wallet and wallet-to-wallet-transfers
> >         the talers.
> >         
> >         
> >         - I use the Taler Cashier app.
> >         
> >         
> >         
> >         However, whenever I select "Send funds" in my wallet and try to
> >         send to a different wallet, i get:
> >         
> >         
> >         "Let the payee scan this QR code to receive: 7001 (unexpected
> >         exception (message: insufficient balance)) [no QR code is
> >         displayed]"
> >         
> >         
> >       
>       >
>       
> >         
> >         What is the issue here? I definitely have enough balance in my
> >         "MANA" currency.
> >         
> >         
> >       
>       
>       Enough inside your wallet (does the MANA balance show in your
>       app?) Clearly at least the error message is bad here, but maybe
>       something else is going on. If you put the wallet into developer
>       mode and export the database (there is an option to do that),
>       wallet devs (wallet@taler.net) could import the DB and try to see
>       what's going on (assuming your exchange endpoint is reachable over
>       the Internet).
>       
>       
> >         
> >         And when trying to use the cashier app, it wants to be connected
> >         to a bank api (e.g. https://bank.demo.taler.net/demobanks). What
> >         would I specify here? Can I point this to my libeufin sandbox or
> >         the nexus somehow (which URL specifically, and what credentials
> >         do I use for login?)
> >         
> >         
> >       
>       
>       You need to create another (non-exchange) bank account with
>       credentials in the libeufin-sandbox, and then give the respective
>       username/password to the cashier app, using
>       "$ENDPOINT/demobanks/default" for the URL (yes, a bit awkward, on
>       my list to get fixed). Additionally, you either need to have
>       configured the sandbox to allow negative balances OR make a 'fake'
>       wire transfer to that user's bank account to get money into the
>       system to withdraw.
>       
>       
>       Last but not least, if you enable self-registration in
>       libeufin-sandbox, you could also use the $ENDPOINT/webui/ to
>       create accounts and initiate withdrawals.
>       
>       
> >         
> >         
> >         I use the debian bullseye packages and wallet v0.9.0 (20) if
> >         that helps
> >         
> >         
> >       
>       
>       That should be fine.
>       
>       
>       -Christian
>       
>       
>