Credit System

PayPal-integrated billing system with transaction tracking

The credit system allows users to top up their balance via PayPal and use credits to purchase groups and services.

Overview

Credit Balance

Track user credits in EUR

PayPal Integration

Secure payments via PayPal REST API

Transaction History

Complete audit trail

Top-Up Flow

User Journey

User navigates to /credits
Views current balance and transaction history
Clicks "Top Up Credits"
Selects amount (€5-€1000) or enters custom amount
Clicks "Continue to PayPal"
Redirected to PayPal for payment
Completes payment on PayPal
Redirected back to success page
Credits automatically added to balance
Transaction logged in history

Top-Up Amounts

Amount	Quick Select	Use Case
€5		Basic group purchase
€10		Small top-up
€20		Pro group purchase
€50		Enterprise group
€100		Bulk purchase
Custom		Any amount €5-€1000

PayPal Configuration

Sandbox (Testing)

PAYPAL_MODE=sandbox
PAYPAL_CLIENT_ID=your-sandbox-client-id
PAYPAL_CLIENT_SECRET=your-sandbox-client-secret

Get Sandbox Credentials:

Go to PayPal Developer Dashboard
Create a sandbox app
Copy Client ID and Secret

Production

PAYPAL_MODE=live
PAYPAL_CLIENT_ID=your-live-client-id
PAYPAL_CLIENT_SECRET=your-live-client-secret

Before Going Live:

Test thoroughly in sandbox
Create production app in PayPal
Enable SSL/HTTPS
Set up webhook verification
Review PayPal's policies

Transaction Types

Credit Transactions

PayPal Top-Up: User adds credits via PayPal
Admin Credit: Manual credit by admin
Refund: Credits returned

Debit Transactions

Group Purchase: User buys a group
Service Purchase: Other services
Admin Debit: Manual deduction

Database Schema

Tables

`credits`

User credit balances

id, user_id, balance, updated_at

`transactions`

Credit/debit transaction history

id, user_id, type, amount, description, reference_id, created_at

`paypal_payments`

PayPal payment tracking

id, user_id, payment_id, payer_id, amount, status, created_at

API Routes

GET  /credits                    - View balance & history
GET  /credits/topup              - Top-up form
POST /credits/payment/create    - Create PayPal payment
GET  /credits/payment/success   - Payment success callback
GET  /credits/payment/cancel    - Payment cancelled callback

Security Features

Atomic Transactions

Database transactions ensure consistency

PayPal Verification

Signature verification in production

Audit Trail

Complete transaction logging

Documentation