Satsback Module for LaWallet

This module is used to send cashback in sats to users who purchase with LaWallet through LaPOS using LaCard.

Table of Contents

• Flow
• Configuration
• To Do

Flow

1. Bob pays with LaCard in LaPOS (only payments with LaCard are valid, payments with QR code don't work).
2. LaPOS sends an HTTP POST request to the /publish endpoint of LaWallet withinternal-transaction-start, containing Bob's payment to LaPOS
3. Ledger recive the payment and confirms it by sending internal-transaction-ok to LaWallet relay (wss://relay.lawallet.ar).
4. The satsback module subscribes to LaWallet relay to listen for internal-transaction-ok emmited by the Ledger and directed to LaPOS.
5. The module receives the internal-transaction-ok.
6. The module sends an HTTP POST request to /publish endpoint of LaWallet with internal-transaction-start, containing the satsback for Bob.
7. Ledger send internal-transaction-ok to LaWallet relay and Bob recive your satsback. (Don't showing in the map).

NOTE: The satsback module MUST have a LaWallet account.

Configuration

1. Setup environment variables

Copy .env.example to .env and fill the MODULE_PRIVATE_KEY with the private key of LaWallet account

It's necessary to have a LaWallet account to send internal transactions.

cp .env.example .env

2. Setup

Use correct node version

nvm use

Install the dependencies

pnpm i

3. Run in dev mode

pnpm dev

To Do

• Fix minimum amount of satsback
• Add database
  • Add list of volunteers walias (pubkey and sats of voucher)
• Add satsback percentages (normal and volunteers) to environment variables
• makeEvent
  • Volunteers handle
    • Search in db
    • Handle sats remaining
  • Encrypt metadata of conent of event for the ledger send interal transaction
  • Save id of payments to LaPOS in db
  • Save the last timestamp of the last payment in db
• Subscribe to relay with the last timestamp
• Check if events are already recive satsback
• Cache for prisma
  • Volunteers model
  • Events model
• Endpoint to add volunteer
• Add documentation
  • Of the filters
  • Of event that the module can handle and emit
  • Of the database
  • How avoid double satsback
  • How handle relay disconnection
• Dockerize