LiquidSecuritiesPOS

  _      _             _     _  _____                      _ _   _
 | |    (_)           (_)   | |/ ____|                    (_) | (_)
 | |     _  __ _ _   _ _  __| | (___   ___  ___ _   _ _ __ _| |_ _  ___  ___
 | |    | |/ _` | | | | |/ _` |\___ \ / _ \/ __| | | | '__| | __| |/ _ \/ __|
 | |____| | (_| | |_| | | (_| |____) |  __/ (__| |_| | |  | | |_| |  __/\__ \
 |______|_|\__, |\__,_|_|\__,_|_____/ \___|\___|\__,_|_|  |_|\__|_|\___||___/
              | |
              |_|    Demo Blockstream AMP POS

 This is an examples of POS terminal using GDK, python and M5Stack board.
             DON'T USE THIS CODE IN PRODUCTION

M5stack based POS for Blockstream AMP tokens.

• http.server is not ready for a production service
• we don't show how to add a tls certificate
• configurations and mnemonic are saved in the same file in plain text
• we use error messages in json without specific codes
• connection status is not monitored
• printer is not monitored
• payments request are persisted in a local file
• communication is not encrypted
• messages are not signed
• there is not an authentication phase

Install the backend

In a python3 virtual environment install GDK (https://github.com/Blockstream/gdk/releases).

Run the script adding the port number as argument.

python pos_backend.py 80

Available commands

• /status return always a static message
• /assets return the list of accepted assets
• /gaid return Blockstream AMP account GAID
• /balance return the balance of subaccount, if asset argument is passed return the balance of the selected asset, if not pass the list of known assets
• /check check if a payment is performed if the argument pointer is passed (and print information using the thermal printer) or return the list of payment requests
• /address return an address an save request payment (name, asset, amount arguments can be passed on url)
• /summary print the payment request summary on the thermal printer

Install the firmware

Open m5green.ino using Arduino IDE, configure the firmware using your IP and port number.