SpendWise

SpendWise is a modern full-stack application for tracking expenses and managing budgets. It provides a robust backend API for financial management, helping users monitor their spending habits, categorize expenses, and receive insights for better financial control.

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🛠️ Tech Stack

Node.js Backend

Technology	Version	Description
Node.js	v18+	JavaScript runtime environment
Express.js	v4.x	Fast, minimalist web framework
PostgreSQL	v14+	Relational database for data persistence
pg (node-postgres)	v8.x	PostgreSQL client for Node.js
dotenv	v16.x	Environment variable management
cors	v2.x	Cross-Origin Resource Sharing middleware

Python Backend

Technology	Version	Description
Python	v3.9+	Core programming language
FastAPI	v0.104+	Modern, fast web framework for APIs
Uvicorn	v0.24+	Lightning-fast ASGI server
SQLAlchemy	v2.0+	SQL toolkit and ORM
Pydantic	v2.0+	Data validation with type hints
psycopg2	v2.9+	PostgreSQL adapter for Python
asyncpg	v0.29+	Async PostgreSQL driver

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📦 Database Setup

PostgreSQL Installation

1. Download and Install: Visit PostgreSQL website and install for your OS

2. Set up credentials: Use default port 5432 and set a strong password

3. Create database:

   CREATE DATABASE spendwise;

4. Create tables:

   -- User table
   CREATE TABLE user_data (
       user_id SERIAL PRIMARY KEY,
       user_name VARCHAR(100) NOT NULL,
       user_email VARCHAR(255) UNIQUE NOT NULL,
       user_password VARCHAR(255) NOT NULL,
       created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
   );
   
   -- Category table
   CREATE TABLE category (
       cy_id SERIAL PRIMARY KEY,
       user_id INTEGER NOT NULL,
       cy_name VARCHAR(100) NOT NULL,
       FOREIGN KEY (user_id) REFERENCES user_data(user_id) ON DELETE CASCADE
   );
   
   -- Expense table
   CREATE TABLE expense (
       ex_id SERIAL PRIMARY KEY,
       user_id INTEGER NOT NULL,
       cy_id INTEGER NOT NULL,
       ex_amount DECIMAL(10,2) NOT NULL,
       ex_desc TEXT,
       ex_data DATE DEFAULT CURRENT_DATE,
       created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
       FOREIGN KEY (user_id) REFERENCES user_data(user_id) ON DELETE CASCADE,
       FOREIGN KEY (cy_id) REFERENCES category(cy_id) ON DELETE SET NULL
   );
   
   -- Budget table
   CREATE TABLE budget (
       b_id SERIAL PRIMARY KEY,
       user_id INTEGER NOT NULL,
       b_mnth VARCHAR(7) NOT NULL,
       limit_amount DECIMAL(10,2) NOT NULL,
       FOREIGN KEY (user_id) REFERENCES user_data(user_id) ON DELETE CASCADE
   );

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🚀 Node.js Setup

Installation

# Clone repository
git clone https://github.com/yourusername/spendwise.git
cd spendwise

# Install dependencies
npm install

# Create .env file
touch .env

Environment Configuration (.env)

PORT=3001
DB_USER=postgres
DB_HOST=localhost
DB_NAME=spendwise
DB_PASSWORD=your_password
DB_PORT=5432

Database Connection (src/config/db.js)

import pg from 'pg';
import dotenv from 'dotenv';

dotenv.config();
const { Pool } = pg;

const pool = new Pool({
    user: process.env.DB_USER,
    host: process.env.DB_HOST,
    database: process.env.DB_NAME,
    password: process.env.DB_PASSWORD,
    port: process.env.DB_PORT,
});

pool.on('connect', () => console.log('✅ Database connected'));
pool.on('error', (err) => console.error('❌ Database error:', err));

export default pool;

Run Application

# Development
npm run dev

# Production
npm start

API Endpoints

Method	Endpoint	Description
GET	/api/user	Get all users
POST	/api/user	Create user
GET	/api/expenses	Get all expenses
POST	/api/expenses	Create expense
GET	/api/budgets	Get all budgets
POST	/api/budgets	Create budget
GET	/api/categories	Get all categories
POST	/api/categories	Create category

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🐍 Python Setup with FastAPI

Installation

# Create virtual environment
python -m venv venv
source venv/bin/activate  # Mac/Linux
venv\Scripts\activate     # Windows

# Install dependencies
pip install fastapi uvicorn sqlalchemy psycopg2-binary python-dotenv pydantic

Environment Configuration (.env)

DATABASE_URL=postgresql://postgres:your_password@localhost:5432/spendwise

Database Connection (app/database.py)

from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
from dotenv import load_dotenv
import os

load_dotenv()

DATABASE_URL = os.getenv("DATABASE_URL")
engine = create_engine(DATABASE_URL)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
Base = declarative_base()

def get_db():
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()

FastAPI Application (app/main.py)

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware

app = FastAPI(title="SpendWise API", version="1.0.0")

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

@app.get("/")
async def root():
    return {"message": "Welcome to SpendWise API", "docs": "/docs"}

@app.get("/health")
async def health_check():
    return {"status": "healthy"}

Run with Uvicorn

# Development
uvicorn app.main:app --reload

# Production
uvicorn app.main:app --host 0.0.0.0 --port 8000 --workers 4

Access Documentation

• API: http://localhost:8000
• Swagger UI: http://localhost:8000/docs
• ReDoc: http://localhost:8000/redoc

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🤖 Machine Learning Integration

Planned Features

• 📊 Expense Prediction: Forecast future expenses based on historical data
• 🎯 Smart Budgeting: AI-driven budget recommendations
• 🔍 Pattern Analysis: Identify spending trends and habits
• ⚠️ Anomaly Detection: Detect unusual transactions and fraud
• 💡 Financial Insights: Personalized money-saving tips

Status: Research and planning phase
Timeline: Integration planned for 2025-2026

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🤝 Contributing

1. Fork the repository
2. Create feature branch (git checkout -b feature/AmazingFeature)
3. Commit changes (git commit -m 'Add AmazingFeature')
4. Push to branch (git push origin feature/AmazingFeature)
5. Open Pull Request

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📄 License

MIT License - see LICENSE file for details.

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⚡ Built with ❤️ for smart financial management