Employee Management System (EMS) Backend

A robust REST API for managing an Employee Management System built with Node.js, Express, and MongoDB.

Features

• Authentication: JWT-based secure authentication & role-based route authorization.
• Master Data Management: Full CRUD operations for Employees, Designations, Locations, Departments, Clients, Projects, and Purchase Orders (POs).
• Transaction Management: Endpoints for Leave Requests, Project Resource Allocations, and PO Allocations Tracking.
• Swagger Documentation: Live, interactive API documentation exposed via Swagger UI.
• Seed Script: Built-in script to instantly deploy fully populated relational dummy data.

Technologies Used

• Node.js & Express.js
• MongoDB (Mongoose ODM)
• JSON Web Tokens (JWT)
• Bcryptjs (password hashing)
• Swagger UI (swagger-jsdoc & swagger-ui-express)

Project Structure

├── config/              # Configuration files (Database connection)
├── controllers/         # API Route Handlers (Logic)
├── middleware/          # Custom auth, role, and error handling middleware
├── models/              # Mongoose DB Schemas
├── routes/              # Express API Route definitions
├── swagger/             # Swagger UI config & schema definitions
├── .env                 # Environment variables (DB URI, JWT Secret)
├── seed.js              # Database dummy data injection script
└── server.js            # Main application entry point

Getting Started

Prerequisites

• Node.js installed
• MongoDB connection string (Local or MongoDB Atlas)

Installation

1. Install dependencies:

   npm install

2. Configure environment variables. Create a .env file in the root with:

   PORT=5000
   MONGO_URI=your_mongodb_connection_string
   JWT_SECRET=your_jwt_secret_key

3. (Optional) Run the seed script to populate test data into your database.

   node seed.js

Running the Project

Development Mode (Nodemon):

npm run dev

Production Mode:

npm start

Available Roles

The system operates with 4 distinct roles, saved in the database as numbers:

• 1 - Super Admin
• 2 - Manager
• 3 - Team Lead
• 4 - Employee

When logging in utilizing the seeded data, you can authenticate via the /api/auth/login endpoint using:

• Super Admin: admin@ems.com / password123
• Employee: john.doe@ems.com / password123

API Documentation

Once the server is running, the interactive Swagger UI can be found at:
👉 http://localhost:5000/api-docs

The Swagger UI provides real-time testing capabilities and data schemas for:

• /api/auth
• /api/employees
• /api/designations
• /api/locations
• /api/departments
• /api/clients
• /api/projects
• /api/pos
• /api/leaves
• /api/allocations
• /api/po-allocations