LockedIn Backend powers the core services of the LockedIn cross-platform application. Built using Node.js, it handles authentication, user data, job listings, media uploads, and payment processing, enabling a seamless and secure professional networking experience.

• JWT-based Authentication: Secure, stateless user sessions

• Firebase OAuth: Google sign-in via Firebase

• Password Management: Encrypted reset and update

• Role-based Access Control

• Input Validation: Ensures secure and clean data

• User CRUD: Create, retrieve, update, delete users

• Experience & Education: Add professional milestones

• Skills Management: Showcase technical abilities

• Media Upload: Upload avatars, resumes via Cloudinary

• Connection Requests: Request/accept/reject connections

• Followers: Follow professionals without direct connections

• Activity Feed: Track updates and posts

• Job Management: Post, edit, and delete job listings

• Application Submission: Apply to jobs directly

• Application Tracking: View job status and history

• Company Profiles: View details of employers

• Real-time Notifications via Firebase Cloud Messaging

• Custom Notification Channels

• Activity-based Alerts

• Stripe Integration: Payments and subscriptions

• Checkout Sessions: Secure checkout for premium features

• Webhook Events: Handle updates from Stripe in real-time

• Node.js – JavaScript runtime

• Express.js – Web framework

• MongoDB + Mongoose – NoSQL database and schema modeling

• Firebase Admin SDK – OAuth and messaging

• Cloudinary – Media storage and transformations

• Stripe API – Payment processing

• JWT – Token-based authentication

• dotenv – Environment configuration

• Multer – File upload middleware

• CORS – Cross-Origin Resource Sharing

• Node.js (v18+ recommended)

• MongoDB Atlas or local instance

• Firebase Project

• Stripe Account

• Cloudinary Account

# Clone the repository
git clone https://github.com/tahaaa22/ClinkedIn/Backend.git
cd Backend

npm install 🔐 Environment Setup Create a .env file in the root directory:

 
 # 🧠 reCAPTCHA
 RECAPTCHA_SECRET_KEY=your-recaptcha-secret-key
 # 🍃 MongoDB
 MONGO_URI=mongodb+srv://<username>:<password>@cluster.mongodb.net/LockedIn
 MONGODB_CONNECTION=mongodb+srv://<username>:<password>@cluster.mongodb.net/LockedIn
 # 🔥 Firebase Admin SDK 
 FIREBASE_TYPE=service_account
 FIREBASE_PROJECT_ID=your-project-id
 FIREBASE_PRIVATE_KEY_ID=your-private-key-id
 FIREBASE_PRIVATE_KEY="-----BEGIN PRIVATE KEY-----\nYOUR-PRIVATE-KEY\n-----END PRIVATE KEY-----\n"
 FIREBASE_CLIENT_EMAIL=your-client-email
 FIREBASE_CLIENT_ID=your-client-id
 FIREBASE_AUTH_URI=https://accounts.google.com/o/oauth2/auth
 FIREBASE_TOKEN_URI=https://oauth2.googleapis.com/token
 FIREBASE_AUTH_PROVIDER_CERT_URL=https://www.googleapis.com/oauth2/v1/certs
 FIREBASE_CLIENT_CERT_URL=https://www.googleapis.com/robot/v1/metadata/x509/firebase-adminsdk@your-project-id.iam.gserviceaccount.com
 FIREBASE_UNIVERSE_DOMAIN=googleapis.com
 # 🔐 JWT Tokens
 ACCESS_TOKEN_SECRET=your-access-token-secret
 REFRESH_TOKEN_SECRET=your-refresh-token-secret
 REFRESH_TOKEN_PATH=/refresh_token
 # ☁️ Cloudinary
 CLOUDINARY_CLOUD_NAME=your-cloud-name
 CLOUDINARY_API_KEY=your-cloudinary-api-key
 CLOUDINARY_API_SECRET=your-cloudinary-api-secret
 # 🌐 App Base URL BASE_URL=http://localhost:3000
 # 📧 Email Service LOCKEDIN_EMAIL=your-email@example.com
 EMAIL_PASSWORD=your-email-app-password

⚠️ Important: Make sure FIREBASE_PRIVATE_KEY is properly escaped or use a JSON key file.

 
 npm run devStart 
 

The server will start on http://localhost:3000 (or your configured port).

LockedIn-Backend/ ├── controllers/ # Request handlers ├── models/ # Mongoose schemas ├── routes/ # API endpoints ├── middlewares/ # Auth, validation, error handling ├── utils/ # Helper functions └── server.js # App entry point

• Authentication – Register/login (email or Google OAuth)

• Profile Setup – Users complete professional details

• Networking – Follow or connect with other users

• Job Exploration – Discover and apply to jobs

• Payment & Upgrade – Purchase premium plans

• Notifications – Get real-time updates via FCM

📘 Full API documentation via Swagger on /api/docs.

 npm run test

Use Jest for unit/integration testing.

Contributions are welcome! Feel free to fork the repo, create a new branch, and submit a Pull Request.

LockedIn Backend – Powering meaningful professional connections.
Built with ❤️ using Node.js and open-source technologies.