💰 Spender Backend

A Go-based expense tracking API that uses Gemini AI to parse natural language text (like SMS or chat) into structured financial transactions.

🚀 Features

• AI Parsing: Converts "Spent 25 USD on coffee" into structured JSON using Gemini 1.5 Flash.
• Asynchronous Processing: Uses Redis and a worker pattern to handle AI requests without slowing down the API.
• Secure Auth: JWT-based authentication and Bcrypt password hashing.
• Infrastructure as Code: Fully containerized Postgres and Redis setup.

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🛠️ Prerequisites

• Go 1.21+
• Docker & Docker Compose
• Gemini API Key

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⚙️ Setup & Installation

1. Clone the repository

git clone https://github.com/yourusername/spender-backend.git
cd spender-backend

2. Configure Environment Variables

Create a .env file in the root directory:

# Database & Redis
DATABASE_URL=postgres://postgres:postgres@localhost:5432/spender?sslmode=disable
REDIS_ADDR=localhost:6379

# Secrets
JWT_SECRET=your_random_secret_string
GEMINI_API_KEY=your_google_api_key_here

3. Start Infrastructure (Databases)

docker-compose up -d postgres redis migrate

4. Run the Application

go mod tidy
go run cmd/apis/main.go

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📡 API Endpoints

Method	Endpoint	Description	Auth Required
POST	/register	Create a new account	No
POST	/login	Get JWT access token	No
POST	/api/notify	Send raw text for AI parsing	Yes

Example Request (/api/notify)

curl -X POST http://localhost:8080/api/notify \
  -H "Authorization: Bearer <YOUR_TOKEN>" \
  -d '{"rawText": "Dinner at Five Guys for 50 AED"}'

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📂 Project Structure

• cmd/ - Application entry points.
• internal/domain/ - Business logic interfaces and models.
• internal/service/ - Core logic (Auth, Engine, AI integration).
• internal/repository/ - Database and Redis implementations.
• migration/ - SQL schema files.

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🧪 Testing

To verify the database tables were created:

docker exec -it spender_db psql -U postgres -d spender -c "\dt"