🎒 GotYourBack - Campus Item Lending and Borrowing Platform

A full-stack web application enabling students to lend, borrow, or sell items within their campus community. Built for SRM students to promote collaboration, sustainability, and easy resource sharing.

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📘 Overview

GotYourBack is a campus-exclusive platform designed to help SRM students lend, borrow, and sell academic or personal items within their community. It promotes collaboration, sustainability, and accessibility by simplifying how students share essential resources.

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🧭 Table of Contents

• Quick Start Guide
• Features
• Technology Stack
• Database Schema
• API Reference
• Security Features
• Testing Guide
• Troubleshooting

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🚀 Quick Start Guide

Prerequisites

• MySQL 8.0+
• Java 17+
• Maven 3.6+
• Modern web browser
• Live Server extension (VS Code) or any HTTP server

Setup in 5 Minutes

1. Clone Repository

git clone https://github.com/atharvpatil18/GotYourBack.git
cd GotYourBack

2. Database Setup

cd Backend
mysql -u root -p < src/main/resources/db/DB_SETUP.sql
# Enter your MySQL root password

3. Configure Backend (if needed)

Edit Backend/src/main/resources/application.yml:

spring:
  datasource:
    password: your_mysql_password

4. Start Backend

mvn spring-boot:run

✅ Backend runs on http://localhost:8080

5. Start Frontend

• Open Frontend/index.html with Live Server
• Or visit http://localhost:5500

6. Create Account & Login

• Visit /signup.html
• Use your email to register
• Login and start sharing!

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✨ Key Features

│ │ ├── service/ # Business logic layer

│ │ ├── model/ # JPA entities---

│ │ ├── dto/ # Data transfer objects

│ │ ├── repository/ # Database repositories## 🎯 Purpose & Impact

│ │ ├── config/ # Security & CORS config

✨ Key Features

📚 Core Functionality

• Post Items: List items to lend or sell with details and images
• Browse & Search: Filter by category, type, urgency, keywords
• Request System: Send, accept, or reject requests
• Real-time Messaging: Chat with users for accepted requests
• Smart Notifications: Get notified of all activities
• Profile Management: Update personal details

🔄 Complete Transaction Workflow

For LEND Items (Full Handover Tracking):

1. Borrower sends REQUEST
   ↓
2. Owner ACCEPTS request
   ↓
3. Owner clicks "Mark as Lent" (when handing over item)
   ↓
4. Borrower clicks "Confirm Receipt" (when receiving item)
   ↓
5. Either party clicks "Mark as Done" (transaction in use)
   ↓
6. Both parties "Confirm Return" (when item returned)
   ↓
7. Item status → AVAILABLE (back in browse)

For SELL Items (Simplified):

1. Buyer sends REQUEST
   ↓
2. Seller ACCEPTS
   ↓
3. Either clicks "Mark as Done"
   ↓
4. Transaction COMPLETE

🔔 Notification System

Automatic notifications for:

• New requests received
• Request accepted/rejected
• Item marked as lent
• Receipt confirmed
• New messages received
• Return confirmations
• Transaction completed

💬 Messaging System

• Private messaging for accepted requests
• Real-time message threads
• Message history
• Organized by conversation

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🧱 Technology Stack

Backend

Component	Technology
Framework	Spring Boot 3.5.6
Database	MySQL 8.0
ORM	JPA/Hibernate
Security	BCrypt Password Hashing
Build Tool	Maven
API Style	RESTful

Frontend

Component	Technology
Core	Vanilla JavaScript (ES6 Modules)
UI Framework	Bootstrap 5
Icons	Bootstrap Icons
HTTP Client	Fetch API
Architecture	MVC Pattern

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📊 Database Schema

Tables Overview

users               # User accounts
items               # Items for lending/selling  
requests            # Borrowing/buying requests
messages            # User-to-user messages
notifications       # Activity notifications

Key Entities & Relationships

Users (users)

• Fields: id, name, email, password, department, registration_number, year_of_study
• Relations: → items (one-to-many), → requests (one-to-many)

Items (items)

• Fields: id, name, description, category, type, status, urgency, image_url, owner_id
• Types: LEND, SELL
• Status: AVAILABLE, SOLD, RETURNED, UNAVAILABLE

Requests (requests)

• Fields: id, item_id, requester_id, status, timestamps
• Status: PENDING, ACCEPTED, REJECTED, DONE
• Tracking: lent_at, received_at, completed_at
• Confirmations: lender_marked_as_lent, borrower_confirmed_receipt

Messages (messages)

• Fields: id, request_id, sender_id, receiver_id, content, sent_at

Notifications (notifications)

• Fields: id, recipient_id, notification_type, message, is_read, timestamps

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🛡️ Security Features

✅ Authentication & Authorization

• BCrypt password hashing (10 rounds)
• Session-based authentication
• Ownership verification for all actions

✅ Input Validation

• Frontend validation
• Backend validation with custom exceptions
• SQL injection prevention (JPA/Hibernate)

✅ XSS Prevention

• DOM-based rendering (no innerHTML for user content)
• Content sanitization

✅ CORS Configuration

• Controlled origins
• Credentials support

✅ Error Handling

• Global exception handler
• Custom exception types
• User-friendly error messages

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📡 API Reference

Authentication

POST   /api/auth/signup          Create new account
POST   /api/auth/login           User login

Items

GET    /api/items                Browse all items
GET    /api/items/{id}           Get item by ID
POST   /api/items                Create new item
PUT    /api/items/{id}           Update item
DELETE /api/items/{id}           Delete item
GET    /api/items/user/{userId}  Get user's items

Requests

GET    /api/requests/user/{userId}              Get user's sent requests
GET    /api/requests/received/{userId}          Get received requests
GET    /api/requests/user/{userId}/accepted     Get accepted requests
POST   /api/requests                            Create request
PUT    /api/requests/{id}/status                Update request status
PUT    /api/requests/{id}/done                  Mark as done
PUT    /api/requests/{id}/mark-as-lent          Owner marks as lent
PUT    /api/requests/{id}/confirm-receipt       Borrower confirms receipt
PUT    /api/requests/{id}/confirm-return        Confirm return

Messages

GET    /api/messages/user/{userId}              Get user messages
GET    /api/messages/request/{requestId}        Get request messages
POST   /api/messages/send/{requestId}           Send message

Notifications

GET    /api/notifications/{userId}              Get notifications
PUT    /api/notifications/{id}/read             Mark as read
DELETE /api/notifications/{id}                  Delete notification

User Profile

GET    /api/users/{userId}                      Get profile
PUT    /api/users/{userId}                      Update profile

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🐛 Troubleshooting

Backend Issues

Port 8080 Already in Use

# Find process using port 8080
netstat -ano | findstr :8080

# Kill the process
taskkill /PID <PID> /F

# Restart backend
mvn spring-boot:run

Database Connection Error

• Check MySQL is running
• Verify credentials in application.yml
• Ensure database gotyourback exists

Compilation Errors

# Clean and rebuild
mvn clean compile

Frontend Issues

API Calls Failing

• Check backend is running on port 8080
• Open browser console (F12) for errors
• Verify CORS settings

Not Loading Data

• Clear browser cache
• Check if logged in (localStorage has userId)
• Verify API endpoints in api-config.js

Images Not Showing

• Check image URLs are valid
• Verify CORS for image sources

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🧪 Testing Checklist

User Flow Testing

• Sign up new user
• Login with credentials
• Post LEND item
• Post SELL item
• Browse and search items
• Send request to item
• Accept/reject requests
• Mark as lent
• Confirm receipt
• Send/receive messages
• Check notifications
• Mark as done
• Confirm return (both parties)
• Verify item reappears in browse

Edge Cases

• Cannot request own item
• Cannot accept own request
• Duplicate requests prevented
• Proper status transitions
• Ownership verification enforced

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📈 Version History

v1.3.0 - Lend/Receipt Tracking (Current)

• ✅ Added "Mark as Lent" feature for owners
• ✅ Added "Confirm Receipt" feature for borrowers
• ✅ Full handover process tracking
• ✅ Enhanced notifications for all workflow steps
• ✅ Database schema updated with lent/receipt fields

v1.2.0 - Return Confirmation

• ✅ Dual return confirmation (borrower + lender)
• ✅ Automatic item availability after confirmation
• ✅ Completed items removed from browse

v1.1.0 - Security Fixes

• ✅ Fixed duplicate notification bug
• ✅ Removed wildcard CORS
• ✅ Added XSS prevention
• ✅ Implemented ownership verification
• ✅ Added custom exceptions

v1.0.0 - Initial Release

• ✅ Core lending/selling functionality
• ✅ User authentication
• ✅ Messaging system
• ✅ Basic notifications

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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

This project is for educational purposes as part of academic coursework.

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👥 Authors & Support

Project Team: SRM Students Repository: atharvpatil18/GotYourBack

For issues or questions:

• Check existing GitHub issues
• Review troubleshooting section
• Contact project maintainers

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