Finance Tracker API

A personal finance tracking REST API for managing accounts and transactions.

Tech Stack

• Runtime: .NET 9.0, ASP.NET Core Web API
• Database: SQLite (dev) / PostgreSQL / SQL Server (production)
• ORM: Entity Framework Core
• Auth: JWT Bearer tokens + BCrypt password hashing
• Testing: xUnit, integration tests with WebApplicationFactory
• Containerization: Docker, docker-compose

Architecture

┌─────────────────────────────────────┐
│            API Layer                │
│  Controllers · Middleware · Auth    │
│         FinanceTracker.Api          │
└────────────────┬────────────────────┘
                 │
┌────────────────▼────────────────────┐
│         Application Layer           │
│       Services · DTOs · Interfaces  │
│                                     │
├─────────────────────────────────────┤
│           Domain Layer              │
│    Entities: Account, Transaction,  │
│    User · Repository Interfaces     │
│            FinanceTracker           │
├─────────────────────────────────────┤
│        Infrastructure Layer         │
│   EF Core · Repositories · DbContext│
└─────────────────────────────────────┘

Application, Domain, and Infrastructure layers share the FinanceTracker project. FinanceTracker.Api is a separate project.

Features

• Register and login with JWT authentication
• Create and manage accounts per user
• Add, view, and categorize transactions
• Transfer funds between accounts
• Claim-based authorization (users access only their own data)
• Rate limiting on auth endpoints
• Health check endpoint at /health

Running Locally

# from repo root
dotnet run --project FinanceTracker.Api

# or enter the project first
cd FinanceTracker.Api
dotnet run

API runs at http://localhost:5029. Database migrations are applied automatically on startup.

Requires a JWT secret via user secrets:

dotnet user-secrets set "JwtSettings:SecretKey" "your-secret-key-min-32-chars"

Running Tests

dotnet test

Running with Docker

docker-compose up --build

API runs at http://localhost:5029. SQLite database is persisted in ./data/. PostgreSQL is used in production.

API Docs

Interactive Swagger UI available at http://localhost:5029/swagger when running locally.

To authenticate:

1. Register a user by calling POST /api/auth/register with request body:

{
  "email": "user@example.com",
  "password": "Password123"
}

2. POST /api/auth/login with the same body to receive a JWT token.
3. In Swagger, click Authorize and paste the token. All protected endpoints will include it automatically.

Environment Variables

Variable	Description	Example
ConnectionStrings__DefaultConnection	SQLite connection string (fallback)	Data Source=/app/data/finance.db
ConnectionStrings__PostgreSQL	PostgreSQL connection string	Host=...;Database=...;Username=...
ConnectionStrings__SqlServer	SQL Server connection string	Server=...;Database=...;User ID=...
JwtSettings__SecretKey	JWT signing secret (min 32 chars)	your-secret-key-32-chars-minimum
JwtSettings__Issuer	JWT issuer	FinanceTracker
JwtSettings__Audience	JWT audience	FinanceTrackerUsers
Cors__AllowedOrigins	Comma-separated allowed origins	http://localhost:3000