Budget Buddy 💰

A full-stack expense tracking application that allows users to manage their budget by adding, editing, and deleting expenses.

🌐 Live: https://expense-tracker-gjuu.onrender.com

Setup

npm install && npm start

🌱 Environment Setup

1.Create a .env file in the root directory. 2.Add your MongoDB connection string:

MONGO_URI=your_mongo_connection_string

🧩 Features

• User Authentication (Register & Login)
• Add, Edit, and Delete Expenses
• Filter by Category and Date
• Backend Validation with Mongoose
• Protected Routes with JWT
• API Documentation with Swagger

Routers

• auth.js – User authentication routes
• expenses.js – Expense-related CRUD routes

User Model

Includes validation for:

• Name
• Email (validated using regex)
• Password (hashed with bcryptjs)

Email Validation Regex

/^(([^<>()[\]\\.,;:\s@"]+(\.[^<>()[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/

Register User

• Validate - name, email, password - with Mongoose
• Hash Password (with bcryptjs)
• Save User
• Generate Token
• Send Response with Token

Login User

• Validate - email, password - in controller
• If email or password is missing, throw BadRequestError
• Find User
• Compare Passwords
• If no user or password does not match, throw UnauthenticatedError
• If correct, generate Token
• Send Response with Token

Mongoose Errors

• Validation Errors
• Duplicate (Email)
• Cast Error

Security

• helmet – Secure HTTP headers
• cors – Cross-origin resource sharing
• xss-clean – Prevent XSS attacks
• express-rate-limit – Limit repeated requests

Swagger UI

/jobs/{id}:
  parameters:
    - in: path
      name: id
      schema:
        type: string
      required: true
      description: the job id